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1.
bioRxiv ; 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38903064

RESUMO

Endosomal Sorting Complexes Required for Transport (ESCRT) play key roles in protein sorting between membrane-bounded compartments of eukaryotic cells. Homologs of many ESCRT components are identifiable in various groups of archaea, especially in Asgardarchaeota, the archaeal phylum that is currently considered to include the closest relatives of eukaryotes, but not in bacteria. We performed a comprehensive search for ESCRT protein homologs in archaea and reconstructed ESCRT evolution using the phylogenetic tree of Vps4 ATPase (ESCRT IV) as a scaffold, using sensitive protein sequence analysis and comparison of structural models to identify previously unknown ESCRT proteins. Several distinct groups of ESCRT systems in archaea outside of Asgard were identified, including proteins structurally similar to ESCRT-I and ESCRT-II, and several other domains involved in protein sorting in eukaryotes, suggesting an early origin of these components. Additionally, distant homologs of CdvA proteins were identified in Thermoproteales which are likely components of the uncharacterized cell division system in these archaea. We propose an evolutionary scenario for the origin of eukaryotic and Asgard ESCRT complexes from ancestral building blocks, namely, the Vps4 ATPase, ESCRT-III components, wH (winged helix-turn-helix fold) and possibly also coiled-coil, and Vps28-like domains. The Last Archaeal Common Ancestor likely encompassed a complex ESCRT system that was involved in protein sorting. Subsequent evolution involved either simplification, as in the TACK superphylum, where ESCRT was co-opted for cell division, or complexification as in Asgardarchaeota. In Asgardarchaeota, the connection between ESCRT and the ubiquitin system that was previously considered a eukaryotic signature was already established.

2.
bioRxiv ; 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38903122

RESUMO

Bacterial and archaeal genomes encompass numerous operons that typically consist of two to five genes. On larger scales, however, gene order is poorly conserved through the evolution of prokaryotes. Nevertheless, non-random localization of different classes of genes on prokaryotic chromosomes could reflect important functional and evolutionary constraints. We explored the patterns of genomic localization of evolutionarily conserved (ancient) and variable (young) genes across the diversity of bacteria and archaea. Nearly all bacterial and archaeal chromosomes were found to encompass large segments of 100-300 kilobases that were significantly enriched in either ancient or young genes. Similar clustering of genes with lethal knockout phenotype (essential genes) was observed as well. Mathematical modeling of genome evolution suggests that this long-range gene clustering in prokaryotic chromosomes reflects perpetual genome rearrangement driven by a combination of selective and neutral processes rather than evolutionary conservation.

3.
BMC Med Genomics ; 17(1): 146, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802805

RESUMO

BACKGROUND: Dyslipidemia, which is characterized by an unfavorable lipid profile, is a key risk factor for cardiovascular disease (CVD). Understanding the relationships between epigenetic aging and lipid levels may help guide early prevention and treatment efforts for dyslipidemia. METHODS: We used weighted linear regression to cross-sectionally investigate the associations between five measures of epigenetic age acceleration estimated from whole blood DNA methylation (HorvathAge Acceleration, HannumAge Acceleration, PhenoAge Acceleration, GrimAge Acceleration, and DunedinPACE) and four blood lipid measures (total cholesterol (TC), LDL-C, HDL-C, and triglycerides (TG)) in 3,813 participants (mean age = 70 years) from the Health and Retirement Study (HRS). As a sensitivity analysis, we examined the same associations in participants who fasted prior to the blood draw (n = 2,531) and in participants who did not take lipid-lowering medication (n = 1,869). Using interaction models, we also examined whether demographic factors including age, sex, and educational attainment modified the relationships between epigenetic age acceleration and blood lipids. RESULTS: After adjusting for age, race/ethnicity, sex, fasting status, and lipid-lowering medication use, greater epigenetic age acceleration was associated with lower TC, HDL-C, and LDL-C, and higher TG (p < 0.05), although the effect sizes were relatively small (e.g., < 7 mg/dL of TC per standard deviation in epigenetic age acceleration). GrimAge acceleration and DunedinPACE associations with all lipids remained significant after further adjustment for body mass index, smoking status, and educational attainment. These associations were stronger in participants who fasted and who did not use lipid-lowering medication, particularly for LDL-C. We observed the largest number of interactions between DunedinPACE and demographic factors, where the associations with lipids were stronger in younger participants, females, and those with higher educational attainment. CONCLUSION: Multiple measures of epigenetic age acceleration are associated with blood lipid levels in older adults. A greater understanding of how these associations differ across demographic groups can help shed light on the relationships between aging and downstream cardiovascular diseases. The inverse associations between epigenetic age and TC and LDL-C could be due to sample limitations or non-linear relationships between age and these lipids, as both TC and LDL-C decrease faster at older ages.


Assuntos
Envelhecimento , Epigênese Genética , Lipídeos , Humanos , Idoso , Feminino , Masculino , Lipídeos/sangue , Envelhecimento/sangue , Envelhecimento/genética , Estados Unidos , Metilação de DNA , Estudos Transversais , Pessoa de Meia-Idade
4.
Res Sq ; 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38699335

RESUMO

Background: Epigenome-wide association studies have revealed multiple DNA methylation sites (CpGs) associated with alcohol consumption, an important lifestyle risk factor for cardiovascular diseases. Results: We generated an alcohol consumption epigenetic risk score (ERS) based on previously reported 144 alcohol-associated CpGs and examined the association of the ERS with systolic blood pressure (SBP), diastolic blood pressure (DBP), and hypertension (HTN) in 3,898 Framingham Heart Study (FHS) participants. We found an association of alcohol intake with the ERS in the meta-analysis with 0.09 units higher ERS per drink consumed per day (p < 0.0001). Cross-sectional analyses in FHS revealed that a one-unit increment of the ERS was associated with 1.93 mm Hg higher SBP (p = 4.64E-07), 0.68 mm Hg higher DBP (p = 0.006), and an odds ratio of 1.78 for HTN (p < 2E-16). Meta-analysis of the cross-sectional association of the ERS with BP traits in eight independent external cohorts (n = 11,544) showed similar relationships with blood pressure levels, i.e., a one-unit increase in ERS was associated with 0.74 (p = 0.002) and 0.50 (p = 0.0006) mm Hg higher SBP and DBP, but could not confirm the association with hypertension. Longitudinal analyses in FHS (n = 3,260) and five independent external cohorts (n = 4,021) showed that the baseline ERS was not associated with a change in blood pressure over time or with incident HTN. Conclusions: Our findings provide proof-of-concept that utilizing an ERS is a useful approach to capture the recent health consequences of lifestyle behaviors such as alcohol consumption.

5.
Nat Commun ; 15(1): 3699, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38698035

RESUMO

In silico identification of viral anti-CRISPR proteins (Acrs) has relied largely on the guilt-by-association method using known Acrs or anti-CRISPR associated proteins (Acas) as the bait. However, the low number and limited spread of the characterized archaeal Acrs and Aca hinders our ability to identify Acrs using guilt-by-association. Here, based on the observation that the few characterized archaeal Acrs and Aca are transcribed immediately post viral infection, we hypothesize that these genes, and many other unidentified anti-defense genes (ADG), are under the control of conserved regulatory sequences including a strong promoter, which can be used to predict anti-defense genes in archaeal viruses. Using this consensus sequence based method, we identify 354 potential ADGs in 57 archaeal viruses and 6 metagenome-assembled genomes. Experimental validation identified a CRISPR subtype I-A inhibitor and the first virally encoded inhibitor of an archaeal toxin-antitoxin based immune system. We also identify regulatory proteins potentially akin to Acas that can facilitate further identification of ADGs combined with the guilt-by-association approach. These results demonstrate the potential of regulatory sequence analysis for extensive identification of ADGs in viruses of archaea and bacteria.


Assuntos
Archaea , Vírus de Archaea , Vírus de Archaea/genética , Archaea/genética , Archaea/virologia , Archaea/imunologia , Regiões Promotoras Genéticas/genética , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Sequências Reguladoras de Ácido Nucleico/genética , Proteínas Virais/genética , Proteínas Arqueais/genética , Proteínas Arqueais/metabolismo , Metagenoma/genética , Proteínas Associadas a CRISPR/genética , Proteínas Associadas a CRISPR/metabolismo , Sistemas CRISPR-Cas/genética
6.
Elife ; 132024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38739430

RESUMO

A comprehensive census of McrBC systems, among the most common forms of prokaryotic Type IV restriction systems, followed by phylogenetic analysis, reveals their enormous abundance in diverse prokaryotes and a plethora of genomic associations. We focus on a previously uncharacterized branch, which we denote coiled-coil nuclease tandems (CoCoNuTs) for their salient features: the presence of extensive coiled-coil structures and tandem nucleases. The CoCoNuTs alone show extraordinary variety, with three distinct types and multiple subtypes. All CoCoNuTs contain domains predicted to interact with translation system components, such as OB-folds resembling the SmpB protein that binds bacterial transfer-messenger RNA (tmRNA), YTH-like domains that might recognize methylated tmRNA, tRNA, or rRNA, and RNA-binding Hsp70 chaperone homologs, along with RNases, such as HEPN domains, all suggesting that the CoCoNuTs target RNA. Many CoCoNuTs might additionally target DNA, via McrC nuclease homologs. Additional restriction systems, such as Type I RM, BREX, and Druantia Type III, are frequently encoded in the same predicted superoperons. In many of these superoperons, CoCoNuTs are likely regulated by cyclic nucleotides, possibly, RNA fragments with cyclic termini, that bind associated CARF (CRISPR-Associated Rossmann Fold) domains. We hypothesize that the CoCoNuTs, together with the ancillary restriction factors, employ an echeloned defense strategy analogous to that of Type III CRISPR-Cas systems, in which an immune response eliminating virus DNA and/or RNA is launched first, but then, if it fails, an abortive infection response leading to PCD/dormancy via host RNA cleavage takes over.


All organisms, from animals to bacteria, are subject to genetic parasites, such as viruses and transposons. Genetic parasites are pieces of nucleic acids (DNA or RNA) that can use a cell's machinery to copy themselves at the expense of their hosts. This often leads to the host's demise, so organisms evolved many types of defense mechanisms. One of the most ancient and common forms of defense against viruses and transposons is the targeted restriction of nucleic acids, that is, deployment of host enzymes that can destroy or restrict nucleic acids containing specific sequence motifs or modifications. In bacteria, many of the restriction enzymes targeting parasitic genetic elements are formed by fusions of proteins from the so-called McrBC systems with a protein domain called EVE. EVE and other functionally similar domains are a part of proteins that recognize and bind modified bases in nucleic acids. Enzymes can use the ability of these specificity domains to bind modified bases to detect non-host nucleic acids. Bell et al. conducted a comprehensive computational search for McrBC systems and discovered a large and highly diverse branch of this family with unusual characteristic structural and functional domains. These features include regions that form long alpha-helices (coils) that coil with other alpha-helices (known as coiled-coils), as well as several distinct enzymatic domains that break down nucleic acids (known as nucleases). They call these systems CoCoNuTs (coiled-coiled nuclease tandems). All CoCoNuTs contain domains, including EVE-like ones, which are predicted to interact with components of the RNA-based systems responsible for producing proteins in the cell (translation), suggesting that the CoCoNuTs have an important impact on protein abundance and RNA metabolism. Bell et al.'s findings will be of interest to scientists working on prokaryotic immunity and virulence. Furthermore, similarities between CoCoNuTs and components of eukaryotic RNA-degrading systems suggest evolutionary connections between this diverse family of bacterial predicted RNA restriction systems and RNA regulatory pathways of eukaryotes. Further deciphering the mechanisms of CoCoNuTs could shed light on how certain pathways of RNA metabolism and regulation evolved, and how they may contribute to advances in biotechnology.


Assuntos
RNA Bacteriano , RNA Bacteriano/metabolismo , RNA Bacteriano/química , RNA Bacteriano/genética , Filogenia , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Bactérias/genética , Bactérias/metabolismo , RNA/metabolismo , RNA/genética , RNA/química
7.
Mar Drugs ; 22(5)2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38786592

RESUMO

Malnutrition is one of the major factors of bone and cartilage disorders. Pacific cod (Gadus macrocephalus) processing waste is a cheap and highly promising source of bioactive substances, including collagen-derived peptides and amino acids, for bone and cartilage structure stabilization. The addition of these substances to a functional drink is one of the ways to achieve their fast intestinal absorption. Collagen hydrolysate was obtained via enzymatic hydrolysis, ultrafiltration, freeze-drying, and grinding to powder. The lyophilized hydrolysate was a light gray powder with high protein content (>90%), including collagen (about 85% of total protein) and a complete set of essential and non-essential amino acids. The hydrolysate had no observed adverse effect on human mesenchymal stem cell morphology, viability, or proliferation. The hydrolysate was applicable as a protein food supply or a structure-forming food component due to the presence of collagen fiber fragments. An isotonic fitness drink (osmolality 298.1 ± 2.1 mOsm/L) containing hydrolysate and vitamin C as a cofactor in collagen biosynthesis was prepared. The addition of the hydrolysate did not adversely affect its organoleptic parameters. The production of such functional foods and drinks is one of the beneficial ways of fish processing waste utilization.


Assuntos
Osso e Ossos , Cartilagem , Colágeno , Gadiformes , Hidrolisados de Proteína , Animais , Colágeno/metabolismo , Humanos , Cartilagem/efeitos dos fármacos , Cartilagem/metabolismo , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Hidrolisados de Proteína/farmacologia , Hidrolisados de Proteína/química , Células-Tronco Mesenquimais/efeitos dos fármacos , Bebidas , Alimento Funcional , Hidrólise
8.
Aging Ment Health ; : 1-9, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38795364

RESUMO

OBJECTIVES: We examined the extent to which positive affect expression in play interactions between adult children and their parents living with cognitive impairment was associated with lower depressive symptoms and mental health difficulties for both dyad members. Gender differences in positive affect expression were also examined. METHOD: Dyads (N = 126) self-reported their depressive symptoms and mental health difficulties. Dyad members later engaged in a video-recorded play interaction together, and their positive affect expression was observationally coded by trained coders in terms of 'enjoyment', 'laughter', and 'positive affect towards partner'. RESULTS: Findings from mixed models using the Actor Partner Interdependence Model showed that one's partner's positive affect was associated with one's own lower depressive symptoms. There were no significant actor effects or effects of role (parent vs. child). Results also revealed that women expressed more positive affect and had greater mental health difficulties, but not depressive symptoms. We found that one's partner's positive affect expressions were more associated with women's mental health than men's mental health. CONCLUSION: Positive affect expression may be a useful indicator of psychological health in parent-child relationships in which the parent has cognitive impairment. Positive affect may be useful to target in supportive, dyadic, psychosocial interventions.

9.
Sci Adv ; 10(17): eadl0164, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38657076

RESUMO

Type VI CRISPR-Cas systems are among the few CRISPR varieties that target exclusively RNA. The CRISPR RNA-guided, sequence-specific binding of target RNAs, such as phage transcripts, activates the type VI effector, Cas13. Once activated, Cas13 causes collateral RNA cleavage, which induces bacterial cell dormancy, thus protecting the host population from the phage spread. We show here that the principal form of collateral RNA degradation elicited by Leptotrichia shahii Cas13a expressed in Escherichia coli cells is the cleavage of anticodons in a subset of transfer RNAs (tRNAs) with uridine-rich anticodons. This tRNA cleavage is accompanied by inhibition of protein synthesis, thus providing defense from the phages. In addition, Cas13a-mediated tRNA cleavage indirectly activates the RNases of bacterial toxin-antitoxin modules cleaving messenger RNA, which could provide a backup defense. The mechanism of Cas13a-induced antiphage defense resembles that of bacterial anticodon nucleases, which is compatible with the hypothesis that type VI effectors evolved from an abortive infection module encompassing an anticodon nuclease.


Assuntos
Anticódon , Sistemas CRISPR-Cas , Escherichia coli , RNA de Transferência , RNA de Transferência/genética , RNA de Transferência/metabolismo , Anticódon/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Leptotrichia/genética , Leptotrichia/metabolismo , Proteínas Associadas a CRISPR/metabolismo , Proteínas Associadas a CRISPR/genética , Bacteriófagos/genética , Clivagem do RNA
10.
Res Sq ; 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38464171

RESUMO

Background: Dyslipidemia, which is characterized by an unfavorable lipid profile, is a key risk factor for cardiovascular disease (CVD). Understanding the relationships between epigenetic aging and lipid levels may help guide early prevention and treatment efforts for dyslipidemia. Methods: We used weighted linear regression to cross-sectionally investigate the associations between five measures of epigenetic age acceleration estimated from whole blood DNA methylation (HorvathAge Acceleration, HannumAge Acceleration, PhenoAge Acceleration, GrimAge Acceleration, and DunedinPACE) and four blood lipid measures (total cholesterol (TC), LDL-C, HDL-C, and triglycerides (TG)) in 3,813 participants (mean age = 70 years) from the Health and Retirement Study (HRS). As a sensitivity analysis, we examined the same associations in participants who fasted prior to the blood draw (n = and f) and in participants who did not take lipid-lowering medication (n = 1,869). Using interaction models, we also examined whether the relationships between epigenetic age acceleration and blood lipids differ by demographic factors including age, sex, and educational attainment. Results: After adjusting for age, race/ethnicity, sex, fasting status, and lipid-lowering medication use, greater epigenetic age acceleration was associated with lower TC, HDL-C, and LDL-C, and higher TG (p < 0.05). GrimAge acceleration and DunedinPACE associations with all lipids remained significant after further adjusting for body mass index, smoking status, and educational attainment. These associations were stronger in participants who fasted and who did not use lipid-lowering medication, particularly for LDL-C. We observed the largest number of interactions between DunedinPACE and demographic factors, where the associations with lipids were stronger in younger participants, females, and those with higher educational attainment. Conclusion: Epigenetic age acceleration, a powerful biomarker of cellular aging, is highly associated with blood lipid levels in older adults. A greater understanding of how these associations differ across demographic groups can help shed light on the relationships between aging and downstream cardiovascular diseases. The inverse associations between epigenetic age and TC and LDL-C could be due to sample limitations or the non-linear relationship between age and these lipids, as both TC and LDL-C decrease faster at older ages. More studies are needed to further understand the temporal relationships between epigenetic age acceleration on blood lipids and other health outcomes.

11.
medRxiv ; 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38464320

RESUMO

Background: Epigenome-wide association studies have revealed multiple DNA methylation sites (CpGs) associated with alcohol consumption, an important lifestyle risk factor for cardiovascular diseases. Results: We generated an alcohol consumption epigenetic risk score (ERS) based on previously reported 144 alcohol-associated CpGs and examined the association of the ERS with systolic blood pressure (SBP), diastolic blood pressure (DBP), and hypertension (HTN) in 3,898 Framingham Heart Study (FHS) participants. We found an association of alcohol intake with the ERS in the meta-analysis with 0.09 units higher ERS per drink consumed per day (p < 0.0001). Cross-sectional analyses in FHS revealed that a one-unit increment of the ERS was associated with 1.93 mm Hg higher SBP (p = 4.64E-07), 0.68 mm Hg higher DBP (p = 0.006), and an odds ratio of 1.78 for HTN (p < 2E-16). Meta-analysis of the cross-sectional association of the ERS with BP traits in eight independent external cohorts (n = 11,544) showed similar relationships with blood pressure levels, i.e., a one-unit increase in ERS was associated with 0.74 (p = 0.002) and 0.50 (p = 0.0006) mm Hg higher SBP and DBP, but could not confirm the association with hypertension. Longitudinal analyses in FHS (n = 3,260) and five independent external cohorts (n = 4,021) showed that the baseline ERS was not associated with a change in blood pressure over time or with incident HTN. Conclusions: Our findings provide proof-of-concept that utilizing an ERS is a useful approach to capture the recent health consequences of lifestyle behaviors such as alcohol consumption.

12.
Artigo em Inglês | MEDLINE | ID: mdl-38430639

RESUMO

OBJECTIVES: Women tend to ruminate more than men, and are generally more hypervigilant to the emotions of others in order to maintain positive social ties. Thus, compared to men, women may ruminate more when their social partners have greater life stresses. However, the literature on stressful events typically focuses on individuals' experiences and perceptions of stressors experienced by specific social ties such as spousal partners and adult children. The purpose of this study was to examine links between perceptions of a broad array of family and nonfamily social partner stresses and daily rumination among older men and women. METHODS: Adults aged 65 and older (N = 293, 55% women) completed baseline assessments of family and nonfamily life stressors and 5-6 consecutive nightly assessments regarding rumination, interpersonal tensions, worries, and support provision. RESULTS: Multilevel structural equation models revealed that perceptions of greater family and nonfamily life stressors were associated with greater rumination. The links between family stress and rumination varied by gender: family stress was related to greater rumination among women and not men. Moreover, among women, family and nonfamily stress-rumination links were accounted for by greater daily worries about others, and among men, the nonfamily stress-rumination link was due to greater interpersonal tensions as well as daily worries. DISCUSSION: These findings may be due in part to gender role socialization and women's greater kin-keeping and investment in family ties.


Assuntos
Emoções , Estresse Psicológico , Masculino , Humanos , Feminino , Idoso , Estresse Psicológico/psicologia , Ansiedade , Filhos Adultos
13.
J Psychosom Res ; 179: 111622, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38484497

RESUMO

OBJECTIVE: Perseverative thinking (e.g., worry/rumination) is a common response to stress, and can be detrimental to well-being. Sleep may represent an important mechanism by which perseverative thinking is disrupted or amplified from day to day. This study examined the associations between older adults' everyday worry, rumination, and sleep. METHODS: Older adults (N = 270) aged 65-89 completed a baseline interview and morning and evening assessments each day for 5-6 days. Every morning, they indicated their worry toward the day and their sleep duration and disturbances the prior night. Every evening, they rated worry and rumination experienced that day. RESULTS: Multilevel models showed that perseverative thinking predicted worse sleep (i.e., fewer hours of sleep) at the between-person level (B = -0.29, p = .004) but better sleep (i.e., fewer sleep disturbances) at the within-person level (Bs < -0.18, ps < .003). At the within-person level, more hours of sleep (B = -0.06, p = .04) and fewer sleep disturbances (B = 0.10, p < .001) predicted less worry the next morning. Prior night's worry predicted greater next morning's worry, but this association was significant only when older adults reported fewer-than-usual hours of sleep (B = 0.24, p < .001), not when they reported more-than-usual hours of sleep (B = 0.04, p = .61). CONCLUSION: Findings suggest that worry and rumination are intimately linked with sleep and highlight the protective role that better sleep may play in reducing older adults' everyday perseverative thinking.


Assuntos
Transtornos Mentais , Pensamento , Humanos , Idoso , Pensamento/fisiologia , Cognição , Sono , Ansiedade
14.
Nat Microbiol ; 9(3): 712-726, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38443574

RESUMO

Cell division is fundamental to all cellular life. Most archaea depend on either the prokaryotic tubulin homologue FtsZ or the endosomal sorting complex required for transport for division but neither system has been robustly characterized. Here, we show that three of the four photosynthesis reaction centre barrel domain proteins of Haloferax volcanii (renamed cell division proteins B1/2/3 (CdpB1/2/3)) play important roles in cell division. CdpB1 interacts directly with the FtsZ membrane anchor SepF and is essential for cell division, whereas deletion of cdpB2 and cdpB3 causes a major and a minor division defect, respectively. Orthologues of CdpB proteins are also involved in cell division in other haloarchaea, indicating a conserved function of these proteins. Phylogenetic analysis shows that photosynthetic reaction centre barrel proteins are widely distributed among archaea and appear to be central to cell division in most if not all archaea.


Assuntos
Haloferax volcanii , Complexo de Proteínas do Centro de Reação Fotossintética , Filogenia , Divisão Celular , Haloferax volcanii/genética , Fotossíntese
16.
mBio ; 15(3): e0033524, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38380930

RESUMO

Endosomal sorting complexes required for transport (ESCRT) play key roles in protein sorting between membrane-bounded compartments of eukaryotic cells. Homologs of many ESCRT components are identifiable in various groups of archaea, especially in Asgardarchaeota, the archaeal phylum that is currently considered to include the closest relatives of eukaryotes, but not in bacteria. We performed a comprehensive search for ESCRT protein homologs in archaea and reconstructed ESCRT evolution using the phylogenetic tree of Vps4 ATPase (ESCRT IV) as a scaffold and using sensitive protein sequence analysis and comparison of structural models to identify previously unknown ESCRT proteins. Several distinct groups of ESCRT systems in archaea outside of Asgard were identified, including proteins structurally similar to ESCRT-I and ESCRT-II, and several other domains involved in protein sorting in eukaryotes, suggesting an early origin of these components. Additionally, distant homologs of CdvA proteins were identified in Thermoproteales which are likely components of the uncharacterized cell division system in these archaea. We propose an evolutionary scenario for the origin of eukaryotic and Asgard ESCRT complexes from ancestral building blocks, namely, the Vps4 ATPase, ESCRT-III components, wH (winged helix-turn-helix fold) and possibly also coiled-coil, and Vps28-like domains. The last archaeal common ancestor likely encompassed a complex ESCRT system that was involved in protein sorting. Subsequent evolution involved either simplification, as in the TACK superphylum, where ESCRT was co-opted for cell division, or complexification as in Asgardarchaeota. In Asgardarchaeota, the connection between ESCRT and the ubiquitin system that was previously considered a eukaryotic signature was already established.IMPORTANCEAll eukaryotic cells possess complex intracellular membrane organization. Endosomal sorting complexes required for transport (ESCRT) play a central role in membrane remodeling which is essential for cellular functionality in eukaryotes. Recently, it has been shown that Asgard archaea, the archaeal phylum that includes the closest known relatives of eukaryotes, encode homologs of many components of the ESCRT systems. We employed protein sequence and structure comparisons to reconstruct the evolution of ESCRT systems in archaea and identified several previously unknown homologs of ESCRT subunits, some of which can be predicted to participate in cell division. The results of this reconstruction indicate that the last archaeal common ancestor already encoded a complex ESCRT system that was involved in protein sorting. In Asgard archaea, ESCRT systems evolved toward greater complexity, and in particular, the connection between ESCRT and the ubiquitin system that was previously considered a eukaryotic signature was established.


Assuntos
Archaea , Complexos Endossomais de Distribuição Requeridos para Transporte , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Filogenia , Sequência de Aminoácidos , Archaea/metabolismo , Adenosina Trifosfatases/metabolismo , Ubiquitinas/metabolismo
17.
Support Care Cancer ; 32(2): 100, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38214761

RESUMO

OBJECTIVE: Since the implementation of value-based healthcare, there has been a growing emphasis on utilizing patient-reported experience measures (PREMs) to enhance the quality of care. However, the current PREMs are primarily generic and static, whereas healthcare is constantly evolving and encompasses a wide variety of aspects that impact care quality. To continuously improve care requires a dynamic PREM. The aim of this study was to propose an item bank for the establishment of a dynamic and care-specific patient-reported evaluation. METHODS: In co-creation with patients, a mixed methods study was conducted involving: (1) an explorative review of the literature, (2) a focus group analysis with (ex-)patients, (3) qualitative analyses to formulate themes, and (4) a quantitative selection of items by patients and experts through prioritization. RESULTS: Eight existing PREMs were evaluated. After removing duplicates, 141 items were identified. Through qualitative analyses of the focus group in which the patient journey was discussed, eight themes were formulated: "Organization of healthcare," "Competence of healthcare professionals," "Communication," "Information & services," "Patient empowerment," "Continuity & informal care," "Environment," and "Technology." Seven patients and eleven professionals were asked to prioritize what they considered the most important items. From this, an item bank with 76 items was proposed. CONCLUSION: In collaboration with patients and healthcare professionals, we have proposed a PREM-item bank to evaluate the experiences of patients' receiving cancer care in an outpatient clinic. This item bank is the first step to dynamically assess the quality of cancer care provided in an outpatient setting.


Assuntos
Instituições de Assistência Ambulatorial , Neoplasias , Humanos , Grupos Focais , Atenção à Saúde , Pacientes Ambulatoriais , Medidas de Resultados Relatados pelo Paciente , Inquéritos e Questionários , Neoplasias/terapia
18.
Nat Commun ; 15(1): 317, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38182597

RESUMO

Thermus thermophilus bacteriophage P23-45 encodes a giant 5,002-residue tail tape measure protein (TMP) that defines the length of its extraordinarily long tail. Here, we show that the N-terminal portion of P23-45 TMP is an unusual RNA polymerase (RNAP) homologous to cellular RNAPs. The TMP-fused virion RNAP transcribes pre-early phage genes, including a gene that encodes another, non-virion RNAP, that transcribes early and some middle phage genes. We report the crystal structures of both P23-45 RNAPs. The non-virion RNAP has a crab-claw-like architecture. By contrast, the virion RNAP adopts a unique flat structure without a clamp. Structure and sequence comparisons of the P23-45 RNAPs with other RNAPs suggest that, despite the extensive functional differences, the two P23-45 RNAPs originate from an ancient gene duplication in an ancestral phage. Our findings demonstrate striking adaptability of RNAPs that can be attained within a single virus species.


Assuntos
Bacteriófagos , Piridinolcarbamato , Vírion/genética , Bacteriófagos/genética , Técnicas de Tipagem Bacteriana , RNA Polimerases Dirigidas por DNA/genética
19.
mBio ; 15(2): e0309223, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38189270

RESUMO

The identification of microbial genes essential for survival as those with lethal knockout phenotype (LKP) is a common strategy for functional interrogation of genomes. However, interpretation of the LKP is complicated because a substantial fraction of the genes with this phenotype remains poorly functionally characterized. Furthermore, many genes can exhibit LKP not because their products perform essential cellular functions but because their knockout activates the toxicity of other genes (conditionally essential genes). We analyzed the sets of LKP genes for two archaea, Methanococcus maripaludis and Sulfolobus islandicus, using a variety of computational approaches aiming to differentiate between essential and conditionally essential genes and to predict at least a general function for as many of the proteins encoded by these genes as possible. This analysis allowed us to predict the functions of several LKP genes including previously uncharacterized subunit of the GINS protein complex with an essential function in genome replication and of the KEOPS complex that is responsible for an essential tRNA modification as well as GRP protease implicated in protein quality control. Additionally, several novel antitoxins (conditionally essential genes) were predicted, and this prediction was experimentally validated by showing that the deletion of these genes together with the adjacent genes apparently encoding the cognate toxins caused no growth defect. We applied principal component analysis based on sequence and comparative genomic features showing that this approach can separate essential genes from conditionally essential ones and used it to predict essential genes in other archaeal genomes.IMPORTANCEOnly a relatively small fraction of the genes in any bacterium or archaeon is essential for survival as demonstrated by the lethal effect of their disruption. The identification of essential genes and their functions is crucial for understanding fundamental cell biology. However, many of the genes with a lethal knockout phenotype remain poorly functionally characterized, and furthermore, many genes can exhibit this phenotype not because their products perform essential cellular functions but because their knockout activates the toxicity of other genes. We applied state-of-the-art computational methods to predict the functions of a number of uncharacterized genes with the lethal knockout phenotype in two archaeal species and developed a computational approach to predict genes involved in essential functions. These findings advance the current understanding of key functionalities of archaeal cells.


Assuntos
Archaea , Proteínas Arqueais , Archaea/genética , Archaea/metabolismo , Genes Essenciais , Genoma Arqueal , Genômica , Fenótipo , Proteínas Arqueais/genética , Proteínas Arqueais/metabolismo
20.
Gerontologist ; 64(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37487060

RESUMO

BACKGROUND AND OBJECTIVES: Spouses with concordant (i.e., similar) drinking behaviors often report better quality marriages and are married longer compared with those who report discordant drinking behaviors. Less is known regarding whether concordant or discordant patterns have implications for health, as couples grow older. The present study examined whether drinking patterns among older couples are associated with mortality over time. RESEARCH DESIGN AND METHODS: The Health and Retirement Study (HRS) is a nationally representative sample of individuals and their partners (married/cohabiting) over age 50 in the United States, in which participants completed surveys every 2 years. Participants included 4,656 married/cohabiting different-sex couples (9,312 individuals) who completed at least 3 waves of the HRS from 1996 to 2016. Participants reported whether they drank alcohol at all in the last 3 months, and if so, the average amount they drank per week. Mortality data were from 2016. RESULTS: Analyses revealed concordant drinking spouses (both indicated they drank in the last 3 months) survived longer than discordant drinking spouses (1 partner drinks and the other does not) and concordant nondrinking spouses. Analysis of average drinks per week showed a quadratic association with mortality such that light drinking predicted better survival rates among individuals and their partners compared with abstaining and heavy drinking. Further, similar levels of drinking in terms of the amount of drinking were associated with greater survival, particularly among wives. DISCUSSION AND IMPLICATIONS: This study moves the field forward by showing that survival varies as a function of one's own and one's partner's drinking.


Assuntos
Consumo de Bebidas Alcoólicas , Casamento , Humanos , Estados Unidos/epidemiologia , Consumo de Bebidas Alcoólicas/epidemiologia , Cônjuges , Características da Família , Inquéritos e Questionários
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