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Niu F, Liu M, Dong S, Dong X, Wang Y, Cheng C, Chu H, Hu Z, Ma F, Yan P, Lan D, Zhang J, Zhou J, Sun B, Zhang A, Hu J, Zhang X, He S, Cui J, Yuan X, Yang J, Cao L, Luo X. RNA-Seq Transcriptome Analysis and Evolution of OsEBS, a Gene Involved in Enhanced Spikelet Number per Panicle in Rice. Int J Mol Sci 2023; 24:10303. [PMID: 37373450 DOI: 10.3390/ijms241210303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2023] [Revised: 06/08/2023] [Accepted: 06/13/2023] [Indexed: 06/29/2023] Open
Abstract
Spikelet number per panicle (SNP) is one of the most important yield components in rice. Rice ENHANCING BIOMASS AND SPIKELET NUMBER (OsEBS), a gene involved in improved SNP and yield, has been cloned from an accession of Dongxiang wild rice. However, the mechanism of OsEBS increasing rice SNP is poorly understood. In this study, the RNA-Seq technology was used to analyze the transcriptome of wildtype Guichao 2 and OsEBS over-expression line B102 at the heading stage, and analysis of the evolution of OsEBS was also conducted. A total of 5369 differentially expressed genes (DEGs) were identified between Guichao2 and B102, most of which were down-regulated in B102. Analysis of the expression of endogenous hormone-related genes revealed that 63 auxin-related genes were significantly down-regulated in B102. Gene Ontogeny (GO) enrichment analysis showed that the 63 DEGs were mainly enriched in eight GO terms, including auxin-activated signaling pathway, auxin polar transport, auxin transport, basipetal auxin transport, and amino acid transmembrane transport, most of which were directly or indirectly related to polar auxin transport. Kyoto Encyclopedia of Genes and Genomes (KEGG) metabolic pathway analysis further verified that the down-regulated genes related to polar auxin transport had important effects on increased SNP. Analysis of the evolution of OsEBS found that OsEBS was involved in the differentiation of indica and japonica, and the differentiation of OsEBS supported the multi-origin model of rice domestication. Indica (XI) subspecies harbored higher nucleotide diversity than japonica (GJ) subspecies in the OsEBS region, and XI experienced strong balancing selection during evolution, while selection in GJ was neutral. The degree of genetic differentiation between GJ and Bas subspecies was the smallest, while it was the highest between GJ and Aus. Phylogenetic analysis of the Hsp70 family in O. sativa, Brachypodium distachyon, and Arabidopsis thaliana indicated that changes in the sequences of OsEBS were accelerated during evolution. Accelerated evolution and domain loss in OsEBS resulted in neofunctionalization. The results obtained from this study provide an important theoretical basis for high-yield rice breeding.
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Affiliation(s)
- Fuan Niu
- State Key Laboratory of Genetic Engineering and MOE Engineering Research Center of Gene Technology, School of Life Sciences, Fudan University, Shanghai 200438, China
- Key Laboratory of Germplasm Innovation and Genetic Improvement of Grain and Oil Crops (Co-Construction by Ministry and Province), Ministry of Agriculture and Rural Affairs, Crop Breeding and Cultivation Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai 201403, China
| | - Mingyu Liu
- State Key Laboratory of Genetic Engineering and MOE Engineering Research Center of Gene Technology, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Shiqing Dong
- State Key Laboratory of Genetic Engineering and MOE Engineering Research Center of Gene Technology, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Xianxin Dong
- State Key Laboratory of Genetic Engineering and MOE Engineering Research Center of Gene Technology, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Ying Wang
- State Key Laboratory of Genetic Engineering and MOE Engineering Research Center of Gene Technology, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Can Cheng
- Key Laboratory of Germplasm Innovation and Genetic Improvement of Grain and Oil Crops (Co-Construction by Ministry and Province), Ministry of Agriculture and Rural Affairs, Crop Breeding and Cultivation Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai 201403, China
| | - Huangwei Chu
- Key Laboratory of Germplasm Innovation and Genetic Improvement of Grain and Oil Crops (Co-Construction by Ministry and Province), Ministry of Agriculture and Rural Affairs, Crop Breeding and Cultivation Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai 201403, China
| | - Zejun Hu
- Key Laboratory of Germplasm Innovation and Genetic Improvement of Grain and Oil Crops (Co-Construction by Ministry and Province), Ministry of Agriculture and Rural Affairs, Crop Breeding and Cultivation Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai 201403, China
| | - Fuying Ma
- State Key Laboratory of Genetic Engineering and MOE Engineering Research Center of Gene Technology, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Peiwen Yan
- State Key Laboratory of Genetic Engineering and MOE Engineering Research Center of Gene Technology, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Dengyong Lan
- State Key Laboratory of Genetic Engineering and MOE Engineering Research Center of Gene Technology, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Jianming Zhang
- Key Laboratory of Germplasm Innovation and Genetic Improvement of Grain and Oil Crops (Co-Construction by Ministry and Province), Ministry of Agriculture and Rural Affairs, Crop Breeding and Cultivation Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai 201403, China
| | - Jihua Zhou
- Key Laboratory of Germplasm Innovation and Genetic Improvement of Grain and Oil Crops (Co-Construction by Ministry and Province), Ministry of Agriculture and Rural Affairs, Crop Breeding and Cultivation Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai 201403, China
| | - Bin Sun
- Key Laboratory of Germplasm Innovation and Genetic Improvement of Grain and Oil Crops (Co-Construction by Ministry and Province), Ministry of Agriculture and Rural Affairs, Crop Breeding and Cultivation Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai 201403, China
| | - Anpeng Zhang
- Key Laboratory of Germplasm Innovation and Genetic Improvement of Grain and Oil Crops (Co-Construction by Ministry and Province), Ministry of Agriculture and Rural Affairs, Crop Breeding and Cultivation Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai 201403, China
| | - Jian Hu
- State Key Laboratory of Genetic Engineering and MOE Engineering Research Center of Gene Technology, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Xinwei Zhang
- State Key Laboratory of Genetic Engineering and MOE Engineering Research Center of Gene Technology, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Shicong He
- State Key Laboratory of Genetic Engineering and MOE Engineering Research Center of Gene Technology, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Jinhao Cui
- State Key Laboratory of Genetic Engineering and MOE Engineering Research Center of Gene Technology, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Xinyu Yuan
- State Key Laboratory of Genetic Engineering and MOE Engineering Research Center of Gene Technology, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Jinshui Yang
- State Key Laboratory of Genetic Engineering and MOE Engineering Research Center of Gene Technology, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Liming Cao
- Key Laboratory of Germplasm Innovation and Genetic Improvement of Grain and Oil Crops (Co-Construction by Ministry and Province), Ministry of Agriculture and Rural Affairs, Crop Breeding and Cultivation Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai 201403, China
| | - Xiaojin Luo
- State Key Laboratory of Genetic Engineering and MOE Engineering Research Center of Gene Technology, School of Life Sciences, Fudan University, Shanghai 200438, China
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Stapane L, Le Roy N, Hincke MT, Gautron J. The glycoproteins EDIL3 and MFGE8 regulate vesicle-mediated eggshell calcification in a new model for avian biomineralization. J Biol Chem 2019; 294:14526-14545. [PMID: 31358619 DOI: 10.1074/jbc.ra119.009799] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 07/26/2019] [Indexed: 11/06/2022] Open
Abstract
The avian eggshell is a critical physical barrier, which permits extra-uterine development of the embryo. Its formation involves the fastest known biomineralization process in vertebrates. The eggshell consists of proteins and proteoglycans that interact with the mineral phase to impart its specific microstructure and mechanical properties. In this study, we investigated the role of epidermal growth factor (EGF)-like repeats and discoidin-like domains 3 (EDIL3) and milk fat globule-EGF factor 8 (MFGE8), two glycoproteins that are consistently detected in eggshell proteomes. We verified their common evolutionary history and identified the timing of the duplication event giving rise to these two distinct proteins. Edil3/mfge8 chromosomal locations revealed a nested syntenous relationship with other genes (hapln1/hapln3 and vcan/acan) that are also involved in vertebrate calcification. EDIL3 and MFGE8 proteins possess EGF-like and coagulation factor 5/8 (F5/8C) domains, and their 3D structures predicted that they bind calcium and extracellular vesicles. In chicken, we confirmed the presence of EDIL3 and MFGE8 proteins in eggshell, uterine fluid, and uterus. We observed that only edil3 is overexpressed in tissues in which eggshell mineralization takes place and that this overexpression occurs only at the onset of shell calcification. We therefore propose a model in which EDIL3 and, to a lesser extent, MFGE8 proteins guide vesicles containing amorphous calcium carbonate to the mineralization site. This model was supported by the observation that extracellular vesicles accumulate in uterine fluid during eggshell calcification and that they contain high levels of calcium, carbon, and oxygen that correspond to calcium carbonate.
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Affiliation(s)
| | | | - Maxwell T Hincke
- Department of Innovation in Medical Education, Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa K1H 8M5, Canada
| | - Joël Gautron
- BOA, INRA, Université de Tours, 37380 Nouzilly, France
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Kajikawa T, Meshikhes F, Maekawa T, Hajishengallis E, Hosur KB, Abe T, Moss K, Chavakis T, Hajishengallis G. Milk fat globule epidermal growth factor 8 inhibits periodontitis in non-human primates and its gingival crevicular fluid levels can differentiate periodontal health from disease in humans. J Clin Periodontol 2017; 44:472-483. [PMID: 28207941 DOI: 10.1111/jcpe.12707] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/12/2017] [Indexed: 01/24/2023]
Abstract
AIM We have previously shown that the secreted glycoprotein milk fat globule epidermal growth factor 8 (MFG-E8) has anti-inflammatory and anti-osteoclastogenic properties. Our objective was to investigate the potential of MFG-E8 as a diagnostic or therapeutic agent in periodontitis. MATERIALS AND METHODS Periodontitis was induced in non-human primates (NHPs) by placing ligatures around posterior teeth on both halves of the mandible for a split-mouth design: one side was treated with MFG-E8-Fc and the other with Fc control. Disease was assessed by clinical periodontal examinations, radiographic analysis of bone loss, and analysis of cytokine mRNA expression in gingival biopsy samples. Gingival crevicular fluid (GCF) was collected from human healthy volunteers or subjects with gingivitis, chronic moderate periodontitis, or chronic severe periodontitis. Additionally, GCF was collected from a subset of severe periodontitis patients following scaling and root planing (SRP) and after pocket reduction surgery. GCF was analysed to quantify MFG-E8 and periodontitis-relevant cytokines using multiplex assays. RESULTS In NHPs, sites treated with MFG-E8-Fc exhibited significantly less ligature-induced periodontal inflammation and bone loss than Fc control-treated sites. In humans, the GCF levels of MFG-E8 were significantly higher in health than in periodontitis, whereas the reverse was true for the proinflammatory cytokines tested. Consistently, MFG-E8 was elevated in GCF after both non-surgical (SRP) and surgical periodontal treatment of periodontitis patients. CONCLUSION MFG-E8 is, in principle, a novel therapeutic agent and biomarker of periodontitis.
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Affiliation(s)
- Tetsuhiro Kajikawa
- Department of Microbiology, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Fatimah Meshikhes
- Department of Periodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Tomoki Maekawa
- Department of Microbiology, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Evlambia Hajishengallis
- Department of Preventive and Restorative Sciences, Division of Pediatric Dentistry, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Kavita B Hosur
- Department of Microbiology, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Toshiharu Abe
- Department of Microbiology, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Kevin Moss
- Department of Dental Ecology, School of Dentistry, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Triantafyllos Chavakis
- Institute for Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Dresden, Germany
| | - George Hajishengallis
- Department of Microbiology, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
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Cheon YP, Kim CH. Impact of glycosylation on the unimpaired functions of the sperm. Clin Exp Reprod Med 2015; 42:77-85. [PMID: 26473106 PMCID: PMC4604297 DOI: 10.5653/cerm.2015.42.3.77] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Revised: 09/20/2015] [Accepted: 09/20/2015] [Indexed: 12/24/2022] Open
Abstract
One of the key factors of early development is the specification of competence between the oocyte and the sperm, which occurs during gametogenesis. However, the starting point, growth, and maturation for acquiring competence during spermatogenesis and oogenesis in mammals are very different. Spermatogenesis includes spermiogenesis, but such a metamorphosis is not observed during oogenesis. Glycosylation, a ubiquitous modification, is a preliminary requisite for distribution of the structural and functional components of spermatids for metamorphosis. In addition, glycosylation using epididymal or female genital secretory glycans is an important process for the sperm maturation, the acquisition of the potential for fertilization, and the acceleration of early embryo development. However, nonemzymatic unexpected covalent bonding of a carbohydrate and malglycosylation can result in falling fertility rates as shown in the diabetic male. So far, glycosylation during spermatogenesis and the dynamics of the plasma membrane in the process of capacitation and fertilization have been evaluated, and a powerful role of glycosylation in spermatogenesis and early development is also suggested by structural bioinformatics, functional genomics, and functional proteomics. Further understanding of glycosylation is needed to provide a better understanding of fertilization and embryo development and for the development of new diagnostic and therapeutic tools for infertility.
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Affiliation(s)
- Yong-Pil Cheon
- Division of Developmental Biology and Physiology, School of Biosciences and Chemistry, Sungshin Women's University, Seoul, Korea
| | - Chung-Hoon Kim
- Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, Asan Medical Center, College of Medicine, University of Ulsan, Seoul, Korea
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Whittle CA, Johannesson H. Evolutionary dynamics of sex-biased genes in a hermaphrodite fungus. Mol Biol Evol 2013; 30:2435-46. [PMID: 23966547 DOI: 10.1093/molbev/mst143] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Differential gene expression is believed to largely explain sexually dichotomous phenotypes. This phenomenon is especially significant in hermaphrodites, in which male and female sexual tissues have identical genotypes. Sex differences in transcription have been linked to molecular evolution: genes with higher expression in male compared with female sexual tissues (i.e., male-biased genes) have been associated with rapid gene divergence in various animals and plants, implying that selective differences exist among the sexual structures. In the present investigation, we examined expressed sequence tags, microarrays, and gene sequence data from the hermaphroditic fungus Neurospora crassa and confirmed selective differences of genes with disparate expression among male versus female sexual structures in this organism. The results held across various genotypes and stages of sexual development. Furthermore, our data showed that N. crassa comprises a rare example of an organism where female-biased genes evolve rapidly; they exhibited faster evolution at the protein level and reduced optimal codon usage compared with male-biased genes, sexually unbiased genes, and vegetative genes. Female-biased genes also had a greater portion of sites that experienced positive selection and showed stronger signals of selective sweeps than male-biased genes, suggesting that the rapid evolution is at least partly driven by adaptive evolution. Distinctive aspects of the reproductive biology of N. crassa which might explain the rapid evolution of female-biased genes are discussed, particularly the propensity for female-female competition during mating, as well as the multifunctional nature of male structures. The present findings open new opportunities to test hypotheses about sex-biased gene expression and molecular evolution.
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Affiliation(s)
- Carrie A Whittle
- Department of Evolutionary Biology, Uppsala University, Uppsala, Sweden
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The map-1 gene family in root-knot nematodes, Meloidogyne spp.: a set of taxonomically restricted genes specific to clonal species. PLoS One 2012; 7:e38656. [PMID: 22719916 PMCID: PMC3377709 DOI: 10.1371/journal.pone.0038656] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2012] [Accepted: 05/08/2012] [Indexed: 11/21/2022] Open
Abstract
Taxonomically restricted genes (TRGs), i.e., genes that are restricted to a limited subset of phylogenetically related organisms, may be important in adaptation. In parasitic organisms, TRG-encoded proteins are possible determinants of the specificity of host-parasite interactions. In the root-knot nematode (RKN) Meloidogyne incognita, the map-1 gene family encodes expansin-like proteins that are secreted into plant tissues during parasitism, thought to act as effectors to promote successful root infection. MAP-1 proteins exhibit a modular architecture, with variable number and arrangement of 58 and 13-aa domains in their central part. Here, we address the evolutionary origins of this gene family using a combination of bioinformatics and molecular biology approaches. Map-1 genes were solely identified in one single member of the phylum Nematoda, i.e., the genus Meloidogyne, and not detected in any other nematode, thus indicating that the map-1 gene family is indeed a TRG family. A phylogenetic analysis of the distribution of map-1 genes in RKNs further showed that these genes are specifically present in species that reproduce by mitotic parthenogenesis, with the exception of M. floridensis, and could not be detected in RKNs reproducing by either meiotic parthenogenesis or amphimixis. These results highlight the divergence between mitotic and meiotic RKN species as a critical transition in the evolutionary history of these parasites. Analysis of the sequence conservation and organization of repeated domains in map-1 genes suggests that gene duplication(s) together with domain loss/duplication have contributed to the evolution of the map-1 family, and that some strong selection mechanism may be acting upon these genes to maintain their functional role(s) in the specificity of the plant-RKN interactions.
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Abstract
Genes expressed in testes are critical to male reproductive success, affecting spermatogenesis, sperm competition, and sperm-egg interaction. Comparing the evolution of testis proteins at different taxonomic levels can reveal which genes and functional classes are targets of natural and sexual selection and whether the same genes are targets among taxa. Here we examine the evolution of testis-expressed proteins at different levels of divergence among three rodents, mouse (Mus musculus), rat (Rattus norvegicus), and deer mouse (Peromyscus maniculatus), to identify rapidly evolving genes. Comparison of expressed sequence tags (ESTs) from testes suggests that proteins with testis-specific expression evolve more rapidly on average than proteins with maximal expression in other tissues. Genes with the highest rates of evolution have a variety of functional roles including signal transduction, DNA binding, and egg-sperm interaction. Most of these rapidly evolving genes have not been identified previously as targets of selection in comparisons among more divergent mammals. To determine if these genes are evolving rapidly among closely related species, we sequenced 11 of these genes in six Peromyscus species and found evidence for positive selection in five of them. Together, these results demonstrate rapid evolution of functionally diverse testis-expressed proteins in rodents, including the identification of amino acids under lineage-specific selection in Peromyscus. Evidence for positive selection among closely related species suggests that changes in these proteins may have consequences for reproductive isolation.
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Wu HH, Su B. Adaptive evolution of SCML1 in primates, a gene involved in male reproduction. BMC Evol Biol 2008; 8:192. [PMID: 18601738 PMCID: PMC2459175 DOI: 10.1186/1471-2148-8-192] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2008] [Accepted: 07/05/2008] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Genes involved in male reproduction are often the targets of natural and/or sexual selection. SCML1 is a recently identified X-linked gene with preferential expression in testis. To test whether SCML1 is the target of selection in primates, we sequenced and compared the coding region of SCML1 in major primate lineages, and we observed the signature of positive selection in primates. RESULTS We analyzed the molecular evolutionary pattern of SCML1 in diverse primate species, and we observed a strong signature of adaptive evolution which is caused by Darwinian positive selection. When compared with the paralogous genes (SCML2 and SCMH1) of the same family, SCML1 evolved rapidly in primates, which is consistent with the proposed adaptive evolution, suggesting functional modification after gene duplication. Gene expression analysis in rhesus macaques shows that during male sexual maturation, there is a significant expression change in testis, implying that SCML1 likely plays a role in testis development and spermatogenesis. The immunohistochemical data indicates that SCML1 is preferentially expressed in germ stem cells of testis, therefore likely involved in spermatogenesis. CONCLUSION The adaptive evolution of SCML1 in primates provides a new case in understanding the evolutionary process of genes involved in primate male reproduction.
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Affiliation(s)
- Hai-hui Wu
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, PR China.
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Wang X, Zhang J. Rapid evolution of primate ESX1, an X-linked placenta- and testis-expressed homeobox gene. Hum Mol Genet 2007; 16:2053-60. [PMID: 17588961 DOI: 10.1093/hmg/ddm153] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Homeobox genes encode transcription factors that play important roles in various developmental processes and are usually evolutionarily conserved. Here we report a case of rapid evolution of a homeobox gene in humans and non-human primates. ESX1 is an X-linked homeobox gene primarily expressed in the placenta and testis, with physiological functions in placenta/fetus development and spermatogenesis. ESX1 is paternally imprinted in mice, but is not imprinted in humans. We provide evidence for a significantly higher non-synonymous substitution rate than synonymous rate in ESX1 between humans and chimps as well as among a total of 15 primate species. Population genetic data also show signals of recent selective sweeps within humans. Positive selection appears to be concentrated in the C-terminal non-homeodomain region, which has been implicated in regulating human male germ cell division by prohibiting the degradation of cyclins. In contrast, mouse Esx1 has a substantively different C-terminal region subject to strong purifying selection. These and other results suggest that even the fundamental process of spermatogenesis has been targeted by positive selection in primate and human evolution and that mouse may not be a suitable model for studying human reproduction.
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Affiliation(s)
- Xiaoxia Wang
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109, USA
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