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1.
Evolution ; 78(2): 355-363, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37952174

RESUMO

Although sex determination is ubiquitous in vertebrates, mechanisms of sex determination vary from environmentally to genetically influenced. In vertebrates, genetic sex determination is typically accomplished with sex chromosomes. Groups like mammals maintain conserved sex chromosome systems, while sex chromosomes in most vertebrate clades are not conserved across similar evolutionary timescales. One group inferred to have an evolutionarily stable mode of sex determination is Anguimorpha, a clade of charismatic taxa including monitor lizards, Gila monsters, and crocodile lizards. The common ancestor of extant anguimorphs possessed a ZW system that has been retained across the clade. However, the sex chromosome system in the endangered, monotypic family of crocodile lizards (Shinisauridae) has remained elusive. Here, we analyze genomic data to demonstrate that Shinisaurus has replaced the ancestral anguimorph ZW system on LG7 with a novel ZW system on LG3. The linkage group, LG3, corresponds to chromosome 9 in chicken, and this is the first documented use of this syntenic block as a sex chromosome in amniotes. Additionally, this ~1 Mb region harbors approximately 10 genes, including a duplication of the sex-determining transcription factor, Foxl2, critical for the determination and maintenance of sexual differentiation in vertebrates, and thus a putative primary sex-determining gene for Shinisaurus.


Assuntos
Lagartos , Animais , Lagartos/genética , Cromossomos Sexuais , Serpentes/genética , Genoma , Genômica , Processos de Determinação Sexual , Mamíferos/genética
2.
Clin Immunol ; 257: 109842, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37981105

RESUMO

Cardinal features of lupus include elevated B cell activation and autoantibody production with a female sex preponderance. We quantified interactions of sex and genetic variation on the development of autoimmune B-cell phenotypes and autoantibodies in the BXD2 murine model of lupus using a cohort of backcrossed progeny (BXD2 x C57BL/6J) x BXD2. Sex was the key factor leading to increased total IgG, IgG2b, and autoantibodies. The percentage of T-bet+CD11c+ IgD+ activated naive B cells (aNAV) was higher in females and was associated with increased T-bet+CD11c+ IgD- age-related B cells, Fas+GL7+ germinal center B cells, Cxcr5-Icos+ peripheral T-helper cells, and Cxcr5+Icos+ follicular T-helper cells. IFN-ß was elevated in females. Variation in aNAV cells was mapped to Chr 7 in a locus that shows significant interactions between the female sex and heterozygous B/D variant. Our results suggest that activation of naive B cells forms the basis for the female-predominant development of autoantibodies in lupus-susceptible BXD2 mice.


Assuntos
Linfócitos B , Lúpus Eritematoso Sistêmico , Animais , Feminino , Humanos , Masculino , Camundongos , Autoanticorpos , Cruzamentos Genéticos , Centro Germinativo , Lúpus Eritematoso Sistêmico/genética , Camundongos Endogâmicos C57BL , Linfócitos T Auxiliares-Indutores , Caracteres Sexuais
3.
bioRxiv ; 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37461522

RESUMO

Although sex determination is ubiquitous in vertebrates, mechanisms of sex determination vary from environmentally- to genetically-influenced. In vertebrates, genetic sex determination is typically accomplished with sex chromosomes. Groups like mammals maintain conserved sex chromosome systems, while sex chromosomes in most vertebrate clades aren't conserved across similar evolutionary timescales. One group inferred to have an evolutionarily stable mode of sex determination is Anguimorpha, a clade of charismatic taxa including: monitor lizards, Gila monsters, and crocodile lizards. The common ancestor of extant anguimorphs possessed a ZW system that has been retained across the clade. However, the sex chromosome system in the endangered, monotypic family of crocodile lizards (Shinisauridae) has remained elusive. Here, we analyze genomic data to demonstrate that Shinisaurus has replaced the ancestral anguimorph ZW system on LG7 chromosome with a novel ZW system on LG3. The linkage group LG3 corresponds to chromosome 9 in chicken, and this is the first documented use of this syntenic block as a sex chromosome in amniotes. Additionally, this ~1Mb region harbors approximately 10 genes, including a duplication of the sex-determining transcription factor, Foxl2-critical for the determination and maintenance of sexual differentiation in vertebrates, and thus a putative primary sex determining gene for Shinisaurus.

4.
Clin Immunol ; 247: 109239, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36682593

RESUMO

T-helper cytokines interferon gamma (IFNÉ£), interleukin 17 (IL-17) and IL-10 impact systemic lupus erythematosus (SLE) directly and indirectly via modulation of autoAb production. We determined the separate and combined effects on clinical manifestations of SLE (N = 62). IFNÉ£, IL-17 but not IL-10 were significantly elevated in patients with SLE. IFNÉ£ positively correlated with anti-DNA and anti-SSA. IL-17 positively correlated with anti-SSA and was significantly higher in patients with discoid rash and class V LN. IL-10 did not correlate with circulating autoantibodies but was significantly elevated in patients with LN. Patients with LN had elevated plasma levels of anti-DNA and anti-Sm/ribonuclear protein (RNP). Anti-Sm/RNP levels were decreased in patients with acute mucocutaneous manifestations, including photosensitivity and/or malar rash. The study provides critical insights into pathological mechanisms of LN, which could help guide future diagnoses and therapies.


Assuntos
Lúpus Eritematoso Sistêmico , Nefrite Lúpica , Humanos , Citocinas , Interleucina-17 , Estudos Transversais , Autoanticorpos , Linfócitos T , Interferon gama , Anticorpos Antinucleares
5.
J Clin Endocrinol Metab ; 105(3)2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31693131

RESUMO

CONTEXT: Women are at increased risk for depressive symptoms during the menopause transition. Changes in estradiol secretion and presence of vasomotor symptoms (VMS) contribute to perimenopausal depressive symptoms, but links with progesterone have not been investigated. OBJECTIVE: To determine whether estradiol variability, ovulatory levels of progesterone, and VMS burden are independently associated with perimenopausal depressive symptomatology. DESIGN AND INTERVENTION: Depressive symptoms, serum levels of estradiol and progesterone, and VMS frequency were assessed weekly in an 8-week observational study. Association of mood with estradiol variability, ovulatory levels of progesterone, and VMS frequency were estimated using generalized estimating equation models. SETTING: Academic medical center. PATIENTS: Fifty unmedicated perimenopausal women with mild-to-moderate depressive symptoms (mean Montgomery-Åsberg Depression Rating Scale [MADRS] score 15.5 ± 5.3). MAIN OUTCOME MEASURE: Depressive symptoms (MADRS score). RESULTS: During the study, 90.0% of participants had varying estradiol levels, 51.1% had ovulatory progesterone levels, and 90% had VMS. Greater estradiol variability and absence of progesterone levels consistent with ovulation, but not VMS frequency, are associated with higher levels of depressive symptoms (ß = 0.11 [95% confidence interval (95% CI), 0.04 to 0.18; P = 0.001]; ß = -2.62 [95% CI, -4.52 to -0.71; P = 0.007], respectively), after accounting for higher body mass index, lifetime history of depression, and stressful life events. CONCLUSIONS: Increasing dysregulation of ovarian hormones, but not VMS, associates with more depressive symptom burden during perimenopause. These results suggest that perimenopausal mood instability is driven by the underlying hormonal dysregulation of the menopause transition involving changes in both estradiol and progesterone.


Assuntos
Depressão/etiologia , Estradiol/sangue , Perimenopausa/sangue , Perimenopausa/psicologia , Progesterona/sangue , Adulto , Afeto , Depressão/epidemiologia , Feminino , Fogachos , Humanos , Pessoa de Meia-Idade , Ovulação/sangue , Sistema Vasomotor
6.
ACS Synth Biol ; 1(5): 156-62, 2012 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-23651153

RESUMO

Tetracycline-regulated expression systems are widely used to control ectopic gene expression in mammalian cells. However, background or "leaky" expression in the "off" state can limit applications that require control of expression at low levels. In this work we have engineered a tetracycline-regulated expression system with an improved range of control and lower background expression. To lower background expression without diminishing the controllable expression range, we designed a feed-forward scheme that repressed both expression of the gene of interest and the transcriptional activator. By using a tetracycline-responsive repressor that can modify chromatin and repress transcription over short and long distances, we were able to repress these two expression targets using a single tetracycline-responsive genetic element. This dual-targeting repressor/activation system demonstrated decreased background expression in its "off" state and a 25-fold range of expression in response to doxycycline. This study demonstrates that genetic circuits can be improved by leveraging trans-acting factors with long-range capabilities.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Tetraciclina/farmacologia , Engenharia Genética , Proteínas de Fluorescência Verde/genética , Células HEK293 , Humanos , Modelos Genéticos , Proteínas Repressoras/genética , Biologia Sintética , Transativadores/genética , Ativação Transcricional/efeitos dos fármacos
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