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1.
Eur J Psychotraumatol ; 15(1): 2364469, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38957142

RESUMO

Background: Many youth with posttraumatic stress symptoms (PTSS) do not receive evidence-based care. Internet- and Mobile-Based Interventions (IMIs) comprising evidence-based trauma-focused components can address this gap, but research is scarce. Thus, we investigated the feasibility of a trauma-focused IMI for youth with PTSS.Methods: In a one-arm non-randomized prospective proof-of-concept study, 32 youths aged 15-21 years with clinically relevant PTSS (CATS ≥ 21) received access to a trauma-focused IMI with therapist guidance, comprising nine sessions on an eHealth platform accessible via web-browser. We used a feasibility framework assessing recruitment capability, sample characteristics, data collection, satisfaction, acceptability, study management abilities, safety aspects, and efficacy of the IMI in PTSS severity and related outcomes. Self-rated assessments took place pre-, mid-, post-intervention and at 3-month follow-up and clinician-rated assessments at baseline and post-intervention.Results: The sample mainly consisted of young adult females with interpersonal trauma and high PTSS levels (CATS, M = 31.63, SD = 7.64). The IMI sessions were found useful and comprehensible, whereas feasibility of trauma processing was perceived as difficult. Around one-third of participants (31%) completed the IMI's eight core sessions. The study completer analysis showed a significant reduction with large effects in self-rated PTSS at post-treatment [t(21) = 4.27; p < .001; d = 0.88] and follow-up [t(18) = 3.83; p = .001; d = 0.84], and clinician-rated PTSD severity at post-treatment [t(21) = 4.52; p < .001; d = 0.93]. The intention-to-treat analysis indicated significant reductions for PTSS at post-treatment and follow-up with large effect sizes (d = -0.97- -1.02). All participants experienced at least one negative effect, with the most common being the resurfacing of unpleasant memories (n = 17/22, 77%).Conclusion: The study reached highly burdened young adults. The IMI was accepted in terms of usefulness and comprehensibility but many youths did not complete all sessions. Exploration of strategies to improve adherence in trauma-focused IMIs for youth is warranted, alongside the evaluation of the IMI's efficacy in a subsequent randomized controlled trial.


Youth often lack access to evidence-based care after trauma. This study assessed the feasibility of a trauma-focused internet- and mobile-based intervention with therapist guidance.The intervention was accepted by youths, and the preliminary evaluation of participant responses suggests its efficacy.Future studies should examine strategies to improve adherence and the IMI's efficacy in a RCT.


Assuntos
Estudos de Viabilidade , Transtornos de Estresse Pós-Traumáticos , Humanos , Transtornos de Estresse Pós-Traumáticos/terapia , Feminino , Adolescente , Masculino , Adulto Jovem , Estudos Prospectivos , Intervenção Baseada em Internet , Internet , Telemedicina , Estudo de Prova de Conceito , Aplicativos Móveis
2.
Neurosci Biobehav Rev ; 163: 105751, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38838877

RESUMO

A growing literature has sought to include mental imagery in fear conditioning studies. Imaginal extinction and imagery rescripting are mental imagery-based interventions that reduce conditioned fear. In the current study, we reviewed the recent findings on the efficacy of imaginal extinction and imagery rescripting as interventions to attenuate conditioned fear responses among healthy individuals. In accordance with the PRISMA guidelines, we conducted a literature search in four databases, PubMed, Scopus, Science Direct, and Web of Science to find published original empirical articles involving imagery-based interventions using a fear conditioning paradigm. The inclusion criteria were (i) use of an imagery-based intervention (either imaginal extinction or imagery rescripting), and (ii) use of a differential fear conditioning paradigm. 13 original articles reporting 15 experimental studies were included in the review. The review revealed that imagery-based interventions are effective in reducing conditioned fear. Although studies have shown that imaginal extinction and standard extinction have comparable effects in fear extinction, many studies have not been conducted to confirm the findings, or explore the underlying mechanisms. We also found the need for a standardized intervention protocol to enhance experimental control in intervention-based fear conditioning studies.

3.
Ecol Evol ; 14(6): e11428, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38855316

RESUMO

Organisms inhabiting mountainous regions can experience large vertical environmental changes, and show different ecological characteristics between altitudes, thus facilitating allopatric fragmentation even in geographically close populations. This study compared the life-history patterns of a species of limnephilid caddisfly, Asynarchus sachalinensis, in several genetically differentiated populations between alpine and sub-alpine zones in a temperate mountainous region. We showed that in the sub-alpine populations, larval development started earlier with increasing water temperature in spring, and adult emergence was also earlier. The occurrence of adults was extremely low in mid-summer, probably due to summer diapause, followed by a larger number of ovary-developed females in autumn. On the other hand, in the alpine zone, increasing water temperature was delayed compared to the sub-alpine zone, and larval development occurred from early to mid-summer. Adult emergence and ovary-developed individuals were concentrated in mid-summer. Hence, summer diapause was not observed. These results indicated life-history differences between genetically differentiated populations at different altitudes. As the timing of adult occurrence and ovarian developmental patterns differ between populations at different altitudes, it is possible that reproductive isolation is facilitated or maintained between populations.

4.
Cancers (Basel) ; 16(9)2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38730720

RESUMO

Cancer cells expand rapidly in response to altered intercellular and signaling interactions to achieve the hallmarks of cancer. Impaired cell polarity combined with activated oncogenes is known to promote several hallmarks of cancer, e.g., activating invasion by increased activity of Jun N-terminal kinase (JNK) and sustained proliferative signaling by increased activity of Hippo effector Yorkie (Yki). Thus, JNK, Yki, and their downstream transcription factors have emerged as synergistic drivers of tumor growth through pro-tumor signaling and intercellular interactions like cell competition. However, little is known about the signals that converge onto JNK and Yki in tumor cells and enable tumor cells to achieve the hallmarks of cancer. Here, using mosaic models of cooperative oncogenesis (RasV12,scrib-) in Drosophila, we show that RasV12,scrib- tumor cells grow through the activation of a previously unidentified network comprising Wingless (Wg), Dronc, JNK, and Yki. We show that RasV12,scrib- cells show increased Wg, Dronc, JNK, and Yki signaling, and all these signals are required for the growth of RasV12,scrib- tumors. We report that Wg and Dronc converge onto a JNK-Yki self-reinforcing positive feedback signal-amplification loop that promotes tumor growth. We found that the Wg-Dronc-Yki-JNK molecular network is specifically activated in polarity-impaired tumor cells and not in normal cells, in which apical-basal polarity remains intact. Our findings suggest that the identification of molecular networks may provide significant insights into the key biologically meaningful changes in signaling pathways and paradoxical signals that promote tumorigenesis.

5.
Clin Psychol Psychother ; 31(3): e3010, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38785407

RESUMO

Imaginal retraining (IR) is an approach-avoidance procedure that has shown promising results in previous studies. The aim of the present study was to dismantle the efficacy of IR's components in a randomized controlled trial (RCT). We conducted a RCT with nine conditions comprising eight intervention groups and a waitlist control group (WLC). Alcohol craving (primary outcome), consumption, depressive symptoms, quality of life, subjective appraisal, and side effects were assessed online at baseline, post intervention (6 weeks), and follow-up (12 weeks). The sample consisted of 426 participants (age: M = 47.22, SD = 11.82, women: 50.5%). The intervention groups received instructions for four different components of IR (mood induction, mental avoidance of unhealthy stimuli, motor avoidance of unhealthy stimuli, approach to healthy stimuli) that were each conveyed with or without prior psychoeducation (PE). The intervention was delivered online. At total of 163 individuals (42.9%) used the intervention at least once. No group differences were found for any primary or secondary outcome after Sidák correction. Uncorrected statistics showed effects of significantly decreased alcohol consumption for the approach + PE group in the intention-to-treat and the merged motor avoidance group in the per-protocol analyses at post assessment compared with the WLC. Exploratory moderation analyses revealed that individuals with high visualization skills benefited most. The authors conclude that visualization training and motivational components may increase the efficacy and adherence of IR.


Assuntos
Imagens, Psicoterapia , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Imagens, Psicoterapia/métodos , Resultado do Tratamento , Alcoolismo/psicologia , Alcoolismo/terapia , Alcoolismo/complicações , Qualidade de Vida/psicologia , Fissura
6.
Addict Behav ; 156: 108043, 2024 09.
Artigo em Inglês | MEDLINE | ID: mdl-38718739

RESUMO

Work has identified that metacognitive thought results in desire-based thinking and perpetuates the magnitude and severity of maladaptive behaviour including problematic social media use, and also that one's ingroup identity is related to increasing problematic behaviour. No evidence has ascertained the relative contribution of these as related differential factors in the experience of problematic social media use. The current study explored the comparative importance of components of desire thinking, positive and negative metacognitions and dimensions of ingroup identity on degree of problematic use among 147 current Instagram users. Results showed that for predicting general problematic Instagram use negative metacognitive beliefs and the verbal perseverance component of desire-based thinking were significant. Importantly, however, different factors appeared to be important for predicting distinct aspects of problematic Instagram. For compulsivity indicators, negative metacognitions and verbal perseveration were essential, whereas for the withdrawal component identity centrality (and no other dimensions of identity) and imaginal prefiguration emerge as the sole independent predictors.


Assuntos
Comportamento Compulsivo , Metacognição , Pensamento , Humanos , Masculino , Feminino , Adulto , Comportamento Compulsivo/psicologia , Adulto Jovem , Transtorno de Adição à Internet/psicologia , Mídias Sociais , Identificação Social , Adolescente , Pessoa de Meia-Idade
7.
BMC Biol ; 22(1): 98, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38679694

RESUMO

BACKGROUND: The ability of animals to regenerate damaged tissue is a complex process that involves various cellular mechanisms. As animals age, they lose their regenerative abilities, making it essential to understand the underlying mechanisms that limit regenerative ability during aging. Drosophila melanogaster wing imaginal discs are epithelial structures that can regenerate after tissue injury. While significant research has focused on investigating regenerative responses during larval stages our comprehension of the regenerative potential of pupal wings and the underlying mechanisms contributing to the decline of regenerative responses remains limited. RESULTS: Here, we explore the temporal dynamics during pupal development of the proliferative response triggered by the induction of cell death, a typical regenerative response. Our results indicate that the apoptosis-induced proliferative response can continue until 34 h after puparium formation (APF), beyond this point cell death alone is not sufficient to induce a regenerative response. Under normal circumstances, cell proliferation ceases around 24 h APF. Interestingly, the failure of reinitiating the cell cycle beyond this time point is not attributed to an incapacity to activate the JNK pathway. Instead, our results suggest that the function of the ecdysone-responsive transcription factor E93 is involved in limiting the apoptosis-induced proliferative response during pupal development. CONCLUSIONS: Our study shows that apoptosis can prolong the proliferative period of cells in the wing during pupal development as late as 34 h APF, at least 10 h longer than during normal development. After this time point, the regenerative response is diminished, a process mediated in part by the ecdysone-responsive transcription factor E93.


Assuntos
Apoptose , Proliferação de Células , Proteínas de Drosophila , Drosophila melanogaster , Pupa , Regeneração , Fatores de Transcrição , Asas de Animais , Animais , Asas de Animais/crescimento & desenvolvimento , Asas de Animais/fisiologia , Drosophila melanogaster/fisiologia , Drosophila melanogaster/crescimento & desenvolvimento , Pupa/crescimento & desenvolvimento , Pupa/fisiologia , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/genética , Regeneração/fisiologia
8.
Clin Psychol Rev ; 110: 102427, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38640775

RESUMO

BACKGROUND: In this systematic review, we aimed to synthesise existing research on the phenomenology of mental imagery among high worriers compared to healthy individuals, and to characterise the nature and effectiveness of existing imagery-related interventions in treatment of worry. METHODS: PsycInfo, CENTRAL, EMBASE, Medline, Medline Epub, and PubMed were searched for studies examining the relationship between worry/GAD and mental imagery, or interventions using imagery in treatment of worry/GAD. We assessed study quality and used qualitative narrative synthesis to comprehensively map study results. RESULTS: The search yielded 2589 abstracts that were assessed for eligibility independently by two authors. From this, 183 full texts were screened and 50 qualitatively synthesised. Twenty-seven reported an association between worry/GAD and an aspect of mental imagery. Here, overactive negative and worry imagery, and diminished positive future imagining, were associated with worry/GAD. Twenty-three studies reported an intervention. This literature suggested mixed findings regarding efficacy, including for imaginal exposure as an independent technique for GAD. CONCLUSIONS: Findings support dysfunctional negative imagining and diminished positive prospective imagery in GAD. General imagining abilities remain intact, which is promising for efforts to utilise imagery in treatment. Further research is warranted to develop innovative clinical applications of imagery in treatment of GAD.


Assuntos
Imagens, Psicoterapia , Humanos , Imagens, Psicoterapia/métodos , Transtornos de Ansiedade/terapia , Transtornos de Ansiedade/psicologia , Imaginação/fisiologia , Ansiedade/terapia , Ansiedade/psicologia
9.
Insect Biochem Mol Biol ; 168: 104114, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38552809

RESUMO

The Drosophila hindgut is a classical model to study organogenesis. The adult hindgut originates from the precursor cells in the larval hindgut. However, the territory of these cells has still not been well determined. A ring of wingless (wg)-expressing cells lies at the anterior zone of both the larval and adult hindgut. The larval Wg ring was thought as a portion of precursor of the adult hindgut. By applying a cell lineage tracing tool (G-TRACE), we demonstrate that larval wg-expressing cells have no cell lineage contribution to the adult hindgut. Additionally, adult Wg ring cells do not divide and move posteriorly to replenish the hindgut tissue. Instead, we determine that the precursors of the adult pylorus and ileum are situated in the cubitus interruptus (ci)-expressing cells in the anterior zone, and deduce that the precursor stem cells of the adult rectum locate in the trunk region of the larval pylorus including hedgehog (hh)-expressing cells. Together, this research advances our understanding of cell lineage origins and the development of the Drosophila hindgut.


Assuntos
Proteínas de Drosophila , Drosophila , Animais , Drosophila/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Larva/genética , Larva/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Proteína Wnt1 , Proteínas Hedgehog/genética , Regulação da Expressão Gênica no Desenvolvimento
10.
Biol Open ; 13(2)2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38345430

RESUMO

Automated image quantification workflows have dramatically improved over the past decade, enriching image analysis and enhancing the ability to achieve statistical power. These analyses have proved especially useful for studies in organisms such as Drosophila melanogaster, where it is relatively simple to obtain high sample numbers for downstream analyses. However, the developing wing, an intensively utilized structure in developmental biology, has eluded efficient cell counting workflows due to its highly dense cellular population. Here, we present efficient automated cell counting workflows capable of quantifying cells in the developing wing. Our workflows can count the total number of cells or count cells in clones labeled with a fluorescent nuclear marker in imaginal discs. Moreover, by training a machine-learning algorithm we have developed a workflow capable of segmenting and counting twin-spot labeled nuclei, a challenging problem requiring distinguishing heterozygous and homozygous cells in a background of regionally varying intensity. Our workflows could potentially be applied to any tissue with high cellular density, as they are structure-agnostic, and only require a nuclear label to segment and count cells.


Assuntos
Drosophila , Discos Imaginais , Animais , Drosophila melanogaster , Larva , Núcleo Celular
11.
J Clin Psychol ; 80(6): 1213-1230, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38356250

RESUMO

BACKGROUND: Mental images of feared events are overactive and intrusive in generalized anxiety disorder (GAD). Imagery rescripting involves integration of positive or neutral imagery and corrective information into images to facilitate emotional processing, reduce imagery intrusions, and re-structure underlying schema. Yet only one known study has applied the technique to treatment of worry. The present study aimed first to examine the relationship between trait worry and properties of future-oriented worry images, and second to examine the efficacy of a self-guided imagery rescripting intervention in improving individuals' response to their worries. METHODS: Participants recruited through Amazon Mechanical Turk (N = 365) identified their major worry and wrote the script of a worst-case scenario mental image. Participants were randomized to three conditions: re-writing the same worry image script (exposure), or writing scripts of either one or three positive alternative future-oriented images (rescripting conditions). RESULTS: In preliminary analyses, trait worry negatively predicted participants' ratings of worry images, including valence and ability to cope, and positively predicted distress, anticipated cost, and belief in their negative meaning. In experimental analyses, linear mixed-effects models revealed anxious response and cognitive appraisal of the threat were significantly lower among participants allocated to rescripting relative to exposure. There was no effect of rescripting type. CONCLUSIONS: This investigation demonstrated the impact of a future-oriented imagery rescripting task on anxiety and cognitive biases associated with real worries in an unselected sample. Results may contribute to the development of imagery rescripting interventions for GAD.


Assuntos
Imagens, Psicoterapia , Humanos , Imagens, Psicoterapia/métodos , Feminino , Adulto , Masculino , Adulto Jovem , Ansiedade/terapia , Pessoa de Meia-Idade , Adolescente , Transtornos de Ansiedade/terapia
12.
Curr Biol ; 34(2): 376-388.e7, 2024 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-38215743

RESUMO

What regulates organ size and shape remains one fundamental mystery of modern biology. Research in this area has primarily focused on deciphering the regulation in time and space of growth and cell division, while the contribution of cell death has been overall neglected. This includes studies of the Drosophila wing, one of the best-characterized systems for the study of growth and patterning, undergoing massive growth during larval stage and important morphogenetic remodeling during pupal stage. So far, it has been assumed that cell death was relatively neglectable in this tissue both during larval stage and pupal stage, and as a result, the pattern of growth was usually attributed to the distribution of cell division. Here, using systematic mapping and registration combined with quantitative assessment of clone size and disappearance as well as live imaging, we outline a persistent pattern of cell death and clone elimination emerging in the larval wing disc and persisting during pupal wing morphogenesis. Local variation of cell death is associated with local variation of clone size, pointing to an impact of cell death on local growth that is not fully compensated by proliferation. Using morphometric analyses of adult wing shape and genetic perturbations, we provide evidence that patterned death locally and globally affects adult wing shape and size. This study describes a roadmap for precise assessment of the contribution of cell death to tissue shape and outlines an important instructive role of cell death in modulating quantitatively local growth and morphogenesis of a fast-growing tissue.


Assuntos
Proteínas de Drosophila , Drosophila , Animais , Epitélio/metabolismo , Divisão Celular , Proteínas de Drosophila/metabolismo , Morfogênese/genética , Apoptose , Larva/metabolismo , Pupa/metabolismo , Asas de Animais , Drosophila melanogaster/genética
13.
Genesis ; 62(1): e23561, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37830148

RESUMO

Hox genes encode transcription factors that play an important role in establishing the basic body plan of animals. In Drosophila, Antennapedia is one of the five genes that make up the Antennapedia complex (ANT-C). Antennapedia determines the identity of the second thoracic segment, known as the mesothorax. Misexpression of Antennapedia at different developmental stages changes the identity of the mesothorax, including the muscles, nervous system, and cuticle. In Drosophila, Antennapedia has two distinct promoters highly regulated throughout development by several transcription factors. Antennapedia proteins are found with other transcription factors in different ANTENNAPEDIA transcriptional complexes to regulate multiple subsets of target genes. In this review, we describe the different mechanisms that regulate the expression and function of Antennapedia and the role of this Hox gene in the development of Drosophila.


Assuntos
Proteínas de Drosophila , Fatores de Transcrição , Animais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Homeodomínio/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Drosophila/genética , Drosophila/metabolismo , Drosophila melanogaster/genética
14.
J Mol Cell Biol ; 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38059855

RESUMO

Mutations or dysregulated expression of NF-kappaB activating protein (NKAP) family genes have been found in human cancers. How NKAP family gene mutations promote tumor initiation and progression remains to be determined. Here, we characterized dNKAP, the Drosophila homolog of NKAP, and showed that impaired dNKAP function causes genome instability and tumorigenic growth in a Drosophila epithelial tumor model. dNKAP-knockdown wing imaginal discs exhibit tumorigenic characteristics, including tissue overgrowth, cell invasive behavior, abnormal cell polarity, and cell adhesion defects. dNKAP knockdown causes both R-loop accumulation and DNA damage, indicating the disruption of genome integrity. Further analysis showed that dNKAP knockdown induces c-Jun N-terminal kinase (JNK)-dependent apoptosis and causes changes in cell proliferation in distinct cell populations. Activation of the Notch and JAK/STAT signaling pathways contributes to the tumorigenic growth of dNKAP-knockdown tissues. Furthermore, JNK signaling is essential for dNKAP depletion-mediated cell invasion. Transcriptome analysis of dNKAP-knockdown tissues confirmed the misregulation of signaling pathways involved in promoting tumorigenesis and revealed abnormal regulation of metabolic pathways. dNKAP knockdown and oncogenic Ras, Notch, or Yki mutations show synergies in driving tumorigenesis, further supporting the tumor-suppressive role of dNKAP. In summary, this study demonstrates that dNKAP plays a tumor-suppressive role by preventing genome instability in Drosophila epithelia and thus provides novel insights into the roles of human NKAP family genes in tumor initiation and progression.

15.
Behav Res Ther ; 170: 104409, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37925798

RESUMO

Trauma-focused imagery-based interventions, such as Imagery Rescripting (ImRs) and Imaginal Exposure (ImE), are effective in reducing involuntary re-experiencing in PTSD. However, it has been suggested that they may impair voluntary memory. This study investigates whether ImRs and ImE distort voluntary memory of an analogue trauma. We presented a trauma film to N = 120 healthy participants (Session 1) and randomly allocated them to one of two intervention conditions (receiving one session of ImRs or ImE) or to a no-intervention control condition (NIC) afterwards (Session 2). Voluntary memory was assessed using a free recall (Sessions 2 and 3), and a cued recall as well as a recognition task (both Sessions 3 and 4). The ImRs and ImE groups did not differ from NIC in the cued recall task and the recognition task. However, ImE (compared to ImRs and NIC) led to an increase in correct reported details in the free recall. In sum, the current findings do not suggest that ImRs or ImE impair voluntary memory.


Assuntos
Imagens, Psicoterapia , Transtornos de Estresse Pós-Traumáticos , Humanos , Sinais (Psicologia) , Rememoração Mental , Filmes Cinematográficos , Reconhecimento Psicológico
16.
Front Cell Dev Biol ; 11: 1214539, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37854071

RESUMO

Homeodomain-interacting protein kinases (Hipks) regulate cell proliferation, apoptosis, and tissue development. Overexpression of Hipk in Drosophila causes tumorigenic phenotypes in larval imaginal discs. We find that depletion of Salt-inducible kinases Sik2 or Sik3 can suppress Hipk-induced overgrowth. Furthermore, co-expression of constitutively active forms of Sik2 or Sik3 with Hipk caused significant tissue hyperplasia and tissue distortion, indicating that both Sik2 and Sik3 can synergize with Hipk to promote tumorous phenotypes, accompanied by elevated dMyc, Armadillo/ß-catenin, and the Yorkie target gene expanded. Larvae expressing these hyperplastic growths also display an extended larval phase, characteristic of other Drosophila tumour models. Examination of total protein levels from fly tissues showed that Hipk proteins were reduced when Siks were depleted through RNAi, suggesting that Siks may regulate Hipk protein stability and/or activity. Conversely, expression of constitutively active Siks with Hipk leads to increased Hipk protein levels. Furthermore, Hipk can interact with Sik2 and Sik3 by co-immunoprecipitation. Co-expression of both proteins leads to a mobility shift of Hipk protein, suggesting it is post-translationally modified. In summary, our research demonstrates a novel function of Siks in synergizing with Hipk to promote tumour growth.

17.
Genes Cells ; 28(12): 857-867, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37817293

RESUMO

Drosophila imaginal disc cells can change their identity under stress conditions through transdetermination (TD). Research on TD can help elucidate the in vivo process of cell fate conversion. We previously showed that the overexpression of winged eye (wge) induces eye-to-wing TD in the eye disc and that an insulin-like peptide, Dilp8, is then highly expressed in the disc. Although Dilp8 is known to mediate systemic developmental delay via the Lgr3 receptor, its role in TD remains unknown. This study showed that Dilp8 is expressed in specific cells that do not express eye or wing fate markers during Wge-mediated TD and that the loss of Dilp8 impairs the process of eye-to-wing transition. Thus, Dilp8 plays a pivotal role in the cell fate conversion under wge overexpression. Furthermore, we found that instead of Lgr3, another candidate receptor, Drl, is involved in Wge-mediated TD and acts locally in the eye disc cells. We propose a model in which Dilp8-Drl signaling organizes cell fate conversion in the imaginal disc during TD.


Assuntos
Proteínas de Drosophila , Drosophila , Animais , Diferenciação Celular , Drosophila/genética , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Discos Imaginais/metabolismo , Transdução de Sinais , Asas de Animais/metabolismo
18.
Development ; 150(18)2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37702007

RESUMO

A fundamental goal of developmental biology is to understand how cell and tissue fates are specified. The imaginal discs of Drosophila are excellent model systems for addressing this paradigm as their fate can be redirected when discs regenerate after injury or when key selector genes are misregulated. Here, we show that when Polycomb expression is reduced, the wing selector gene vestigial is ectopically activated. This leads to the inappropriate formation of the Vestigial-Scalloped complex, which forces the eye to transform into a wing. We further demonstrate that disrupting this complex does not simply block wing formation or restore eye development. Instead, immunohistochemistry and high-throughput genomic analysis show that the eye-antennal disc unexpectedly undergoes hyperplastic growth with multiple domains being organized into other imaginal discs and tissues. These findings provide insight into the complex developmental landscape that tissues must navigate before adopting their final fate.


Assuntos
Proteínas de Drosophila , Discos Imaginais , Animais , Proteínas de Drosophila/genética , Drosophila , Genômica , Hiperplasia , Proteínas do Grupo Polycomb/genética
19.
Dev Cell ; 58(20): 2128-2139.e4, 2023 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-37769663

RESUMO

The steroid hormone 20-hydroxy-ecdysone (20E) promotes proliferation in Drosophila wing precursors at low titer but triggers proliferation arrest at high doses. Remarkably, wing precursors proliferate normally in the complete absence of the 20E receptor, suggesting that low-level 20E promotes proliferation by overriding the default anti-proliferative activity of the receptor. By contrast, 20E needs its receptor to arrest proliferation. Dose-response RNA sequencing (RNA-seq) analysis of ex vivo cultured wing precursors identifies genes that are quantitatively activated by 20E across the physiological range, likely comprising positive modulators of proliferation and other genes that are only activated at high doses. We suggest that some of these "high-threshold" genes dominantly suppress the activity of the pro-proliferation genes. We then show mathematically and with synthetic reporters that combinations of basic regulatory elements can recapitulate the behavior of both types of target genes. Thus, a relatively simple genetic circuit can account for the bimodal activity of this hormone.


Assuntos
Proteínas de Drosophila , Receptores de Esteroides , Animais , Drosophila/genética , Proteínas de Drosophila/genética , Ligantes , Receptores de Esteroides/genética , Hormônios , Proliferação de Células , Ecdisona
20.
Insects ; 14(8)2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37623381

RESUMO

The oriental fruit fly, Bactrocera dorsalis (Hendel), is a notorious invasive pest that has raised concerns worldwide. Validamycin has been demonstrated to be a very strong inhibitor against trehalase in a variety of organisms. However, whether validamycin can inhibit trehalase activity to suppress trehalose hydrolysis and affect any other relevant physiological pathways in B. dorsalis remains unknown. In this study, the effects of validamycin injection on the synthesis and metabolism of trehalose and chitin were evaluated. The results show that validamycin injection significantly affected trehalase activity and caused trehalose accumulation. In addition, the downstream pathways of trehalose hydrolysis, including the synthesis and metabolism of chitin, were also remarkably affected as the expressions of the key genes in these pathways were significantly regulated and the chitin contents were changed accordingly. Intriguingly, the upstream trehalose synthesis was also affected by validamycin injection due to the variations in the expression levels of key genes, especially BdTPPC1. Moreover, BdTPPC1 was predicted to have a binding affinity to validamycin, and the subsequent in vitro recombinant enzyme activity assay verified the inhibitory effect of validamycin on BdTPPC1 activity for the first time. These findings collectively indicate that validamycin can be considered as a promising potential insecticide for the management of B. dorsalis.

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