Homo sapiens
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PROVIDER: PRJNA267740 | ENA |
REPOSITORIES: ENA
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Project description:Introduction: Structural integrity of the cervical epithelial barrier is crucial for defending the female reproductive tract against sexually transmitted infections, including HIV. Female sex hormones, estradiol and progesterone, play an important role in modulating this epithelial barrier. However, the influence of fluctuating estradiol and progesterone on ectocervical tissue gene and protein expression in naturally cycling women at high risk for sexually transmitted infections is not well understood. Methods: Ectocervical biopsies, cervicovaginal lavage fluid, and venous blood samples were collected from naturally cycling Kenyan female sex workers at two time points, separated by 2 weeks. The first time point represented the luteal phase of the menstrual cycle and the second time point represented the follicular phase. Plasma estradiol and progesterone levels were measured at each time point. Ectocervical tissues were analyzed by RNA-sequencing and in situ immunofluorescence staining. Cervicovaginal lavage samples were evaluated using antibody-based protein profiling. Results: Employing a systems biology approach, we demonstrated that high plasma estradiol levels enhanced ectocervical epithelial integrity. These findings were more pronounced in samples from the follicular phase (when progesterone and estradiol levels were significantly lower) and included increased expression, and more intact distribution, of the desmosomal cadherin DSG1. The effects of progesterone on gene and protein levels, as well as on intact tissue (as visualized by in situ staining), were modest throughout the menstrual cycle. Both estradiol and progesterone levels had limited influence on mucosal immune factors. Conclusion: Estradiol levels were associated with modulation of cervical epithelial barrier integrity, including the expression and distribution of DSG1, during the follicular phase of natural menstrual cycles in Kenyan sex workers.
2025-01-17 | GSE273823 | GEO
Project description:Kynureninase is a member of a large family of catalytically diverse but structurally homologous pyridoxal 5'-phosphate (PLP) dependent enzymes known as the aspartate aminotransferase superfamily or alpha-family. The Homo sapiens and other eukaryotic constitutive kynureninases preferentially catalyze the hydrolytic cleavage of 3-hydroxy-l-kynurenine to produce 3-hydroxyanthranilate and l-alanine, while l-kynurenine is the substrate of many prokaryotic inducible kynureninases. The human enzyme was cloned with an N-terminal hexahistidine tag, expressed, and purified from a bacterial expression system using Ni metal ion affinity chromatography. Kinetic characterization of the recombinant enzyme reveals classic Michaelis-Menten behavior, with a Km of 28.3 +/- 1.9 microM and a specific activity of 1.75 micromol min-1 mg-1 for 3-hydroxy-dl-kynurenine. Crystals of recombinant kynureninase that diffracted to 2.0 A were obtained, and the atomic structure of the PLP-bound holoenzyme was determined by molecular replacement using the Pseudomonas fluorescens kynureninase structure (PDB entry 1qz9) as the phasing model. A structural superposition with the P. fluorescens kynureninase revealed that these two structures resemble the "open" and "closed" conformations of aspartate aminotransferase. The comparison illustrates the dynamic nature of these proteins' small domains and reveals a role for Arg-434 similar to its role in other AAT alpha-family members. Docking of 3-hydroxy-l-kynurenine into the human kynureninase active site suggests that Asn-333 and His-102 are involved in substrate binding and molecular discrimination between inducible and constitutive kynureninase substrates.
| S-EPMC2531291 | biostudies-literature
Project description:RNA extracted at 240min. Samples are rRNA depleted. Expression measurement of Homo sapiens genes.
2019-07-31 | GSE114179 | GEO
Project description:As the evolution of miRNA genes has been found to be one of the important factors in formation of the modern type of man, we performed a comparative analysis of the evolution of miRNA genes in two archaic hominines, Homo sapiens neanderthalensis and Homo sapiens denisova, and elucidated the expression of their target mRNAs in bain.A comparative analysis of the genomes of primates, including species in the genus Homo, identified a group of miRNA genes having fixed substitutions with important implications for the evolution of Homo sapiens neanderthalensis and Homo sapiens denisova. The mRNAs targeted by miRNAs with mutations specific for Homo sapiens denisova exhibited enhanced expression during postnatal brain development in modern humans. By contrast, the expression of mRNAs targeted by miRNAs bearing variations specific for Homo sapiens neanderthalensis was shown to be enhanced in prenatal brain development.Our results highlight the importance of changes in miRNA gene sequences in the course of Homo sapiens denisova and Homo sapiens neanderthalensis evolution. The genetic alterations of miRNAs regulating the spatiotemporal expression of multiple genes in the prenatal and postnatal brain may contribute to the progressive evolution of brain function, which is consistent with the observations of fine technical and typological properties of tools and decorative items reported from archaeological Denisovan sites. The data also suggest that differential spatial-temporal regulation of gene products promoted by the subspecies-specific mutations in the miRNA genes might have occurred in the brains of Homo sapiens denisova and Homo sapiens neanderthalensis, potentially contributing to the cultural differences between these two archaic hominines.
| S-EPMC4686780 | biostudies-literature
Project description:PurposeWe investigated the evidence of recent positive selection in the human phototransduction system at single nucleotide polymorphism (SNP) and gene level.MethodsSNP genotyping data from the International HapMap Project for European, Eastern Asian, and African populations was used to discover differences in haplotype length and allele frequency between these populations. Numeric selection metrics were computed for each SNP and aggregated into gene-level metrics to measure evidence of recent positive selection. The level of recent positive selection in phototransduction genes was evaluated and compared to a set of genes shown previously to be under recent selection, and a set of highly conserved genes as positive and negative controls, respectively.ResultsSix of 20 phototransduction genes evaluated had gene-level selection metrics above the 90th percentile: RGS9, GNB1, RHO, PDE6G, GNAT1, and SLC24A1. The selection signal across these genes was found to be of similar magnitude to the positive control genes and much greater than the negative control genes.ConclusionsThere is evidence for selective pressure in the genes involved in retinal phototransduction, and traces of this selective pressure can be demonstrated using SNP-level and gene-level metrics of allelic variation. We hypothesize that the selective pressure on these genes was related to their role in low light vision and retinal adaptation to ambient light changes. Uncovering the underlying genetics of evolutionary adaptations in phototransduction not only allows greater understanding of vision and visual diseases, but also the development of patient-specific diagnostic and intervention strategies.
| S-EPMC3743458 | biostudies-literature
Project description:Cortical thickness has been investigated since the beginning of the 20th century, but we do not know how similar the cortical thickness profiles among humans are. In this study, the local similarity of cortical thickness profiles was investigated using sliding window methods. Here, we show that approximately 5% of the cortical thickness profiles are similarly expressed among humans while 45% of the cortical thickness profiles show a high level of heterogeneity. Therefore, heterogeneity is the rule, not the exception. Cortical thickness profiles of somatosensory homunculi and the anterior insula are consistent among humans, while the cortical thickness profiles of the motor homunculus are more variable. Cortical thickness profiles of homunculi that code for muscle position and skin stimulation are highly similar among humans despite large differences in sex, education, and age. This finding suggests that the structure of these cortices remains well preserved over a lifetime. Our observations possibly relativize opinions on cortical plasticity.
| S-EPMC5738339 | biostudies-literature
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
2010-09-25 | GSE24338 | GEO
Project description:Highly Exposed-Seronegatives (HESN) individuals do not contract HIV-1 infection despite long-term exposure; few comprehensive studies examining behavior, mucosal tissue, and peripheral immune parameters in sexually-exposed HESN have been completed. To this end, we assessed rate of condomless vaginal sex, the immune activation status (peripheral blood) and gene expression (ectocervical biopsies) in female cohort of high-risk female sex workers [FSW] (n=50) and non-sex worker women [CG] (n=32) in San Juan, Puerto Rico, USA. Of the 50 FSWs examined only 5 had detectable anti-HIV responses by either HIV gag-specific CD8+ T-Cell responses or mucosal anti-HIV envelope IgG/IgA. FSW had a uniform lower CD38 expression on circulating CD4+ or CD8+ T-Cells (both: p<0.0001:Wilcoxon Rank Sum). Cervical tissue from FSWs had greater levels of CD4+ T-Cell (p=0.040), CD123+ plasmacytoid Dendritic Cells (p=0.013) and CD68+ macrophage infiltrates (p=0.038). Cervical gene expression by RNA microarray indicated that FSW had a gene signature characterized by lower expression of genes associated with leukocyte homing and chemotaxis; partial interferon regulated gene signature; and lower gene expression of genes required for HIV infection such as CD4 and NUP153 indicating a lower mucosal immune activation state and reduced susceptibility to HIV-1 infection within mucosal tissue. Notably, Interferon (IFN)-ε expression was higher in FSW than CG women, as detected by RNA (microarray) and protein (IHC) expression in cervical epithelium. The observed levels of IFNε were associated with the reported frequency of unprotected intercourse. Finally, IFNε was induced by treatment of the ECT1 cell line with seminal fluid, suggesting that semen exposure may contribute to long-term protection. Decreased levels of immune activation and gene expression required for HIV infection along with semen-induced epithelial Interferon ε production within the reproductive tract of FSWs highlight distinct host intrinsic resistance mechanisms that may contribute to long-term HIV seronegative status in spite of high-risk condomless sex.
2019-11-21 | GSE63441 | GEO
Project description:Understanding the timing and character of the expansion of Homo sapiens out of Africa is critical for inferring the colonization and admixture processes that underpin global population history. It has been argued that dispersal out of Africa had an early phase, particularly ~130-90 thousand years ago (ka), that reached only the East Mediterranean Levant, and a later phase, ~60-50 ka, that extended across the diverse environments of Eurasia to Sahul. However, recent findings from East Asia and Sahul challenge this model. Here we show that H. sapiens was in the Arabian Peninsula before 85 ka. We describe the Al Wusta-1 (AW-1) intermediate phalanx from the site of Al Wusta in the Nefud desert, Saudi Arabia. AW-1 is the oldest directly dated fossil of our species outside Africa and the Levant. The palaeoenvironmental context of Al Wusta demonstrates that H. sapiens using Middle Palaeolithic stone tools dispersed into Arabia during a phase of increased precipitation driven by orbital forcing, in association with a primarily African fauna. A Bayesian model incorporating independent chronometric age estimates indicates a chronology for Al Wusta of ~95-86 ka, which we correlate with a humid episode in the later part of Marine Isotope Stage 5 known from various regional records. Al Wusta shows that early dispersals were more spatially and temporally extensive than previously thought. Early H. sapiens dispersals out of Africa were not limited to winter rainfall-fed Levantine Mediterranean woodlands immediately adjacent to Africa, but extended deep into the semi-arid grasslands of Arabia, facilitated by periods of enhanced monsoonal rainfall.
| S-EPMC5935238 | biostudies-literature