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Teng FY, Feng JM, Ma FC, Wang ZX, Lu YY, Qi YX. Characterization of an agmatine N-acetyltransferase from Bactrocera dorsalis that modulates ovary development. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2024; 170:104130. [PMID: 38734116 DOI: 10.1016/j.ibmb.2024.104130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2023] [Revised: 05/07/2024] [Accepted: 05/07/2024] [Indexed: 05/13/2024]
Abstract
Agmatine N-acetyltransferase (AgmNAT), which catalyzes the formation of N-acetylagmatine from acetyl-CoA and agmatine, is a member of the GCN5-related N-acetyltransferase family. So far, knowledge of the physiological roles of AgmNAT in insects is limited. Here, we identified one gene encoding protein homologous to that of Drosophila AgmNAT using sequence information from an activity-verified Drosophila AgmNAT in a BLAST search of the Bactrocera dorsalis genome. We expressed and purified B. dorsalis AgmNAT in Escherichia coli and used the purified enzyme to define the substrate specificity for acyl-CoA and amine substrates. Our application of the screening strategy to BdorAgmNAT led to the identification of agmatine as the best amine substrate for this enzyme, with the highest kcat/Km value. We successfully obtained a BdorAgmNAT knockout strain based on a wild-type strain (WT) using the CRISPR/Cas9 technique. The ovary development of the BdorAgmNAT knockout mutants was delayed for 10 days compared with the WT specimens. Moreover, mutants had a much smaller mature ovary size and laid far fewer eggs than WT. Loss of function of BdorAgmNAT caused by RNAi with mature WT females did not affect their fecundity. These findings indicate that BdorAgmNAT is critical for oogenesis. Our data provide the first evidence for AgmNAT in regulating ovary development.
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Affiliation(s)
- Fei-Yue Teng
- Department of Entomology, College of Plant Protection, South China Agricultural University, Guangzhou, China
| | - Ji-Mei Feng
- Department of Entomology, College of Plant Protection, South China Agricultural University, Guangzhou, China
| | - Fu-Cai Ma
- Department of Entomology, College of Plant Protection, South China Agricultural University, Guangzhou, China
| | - Zhuo-Xin Wang
- Department of Entomology, College of Plant Protection, South China Agricultural University, Guangzhou, China
| | - Yong-Yue Lu
- Department of Entomology, College of Plant Protection, South China Agricultural University, Guangzhou, China
| | - Yi-Xiang Qi
- Department of Entomology, College of Plant Protection, South China Agricultural University, Guangzhou, China.
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2
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Zelinger E, Brumfeld V, Rechav K, Waiger D, Kossovsky T, Heifetz Y. Three-dimensional correlative microscopy of the Drosophila female reproductive tract reveals modes of communication in seminal receptacle sperm storage. Commun Biol 2024; 7:155. [PMID: 38321098 PMCID: PMC10847118 DOI: 10.1038/s42003-024-05829-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Accepted: 01/17/2024] [Indexed: 02/08/2024] Open
Abstract
In many taxa, females store sperm in specialized storage organs. Most insect sperm storage organs have a tubular structure, typically consisting of a central lumen surrounded by epithelial cells. These specialized tubules perform the essential tasks of transporting sperm through the female reproductive tract and supporting long-term sperm survival and function. Little is known about the way in which female sperm storage organs provide an environment conducive to sperm survival. We address this using a combined light microscopy, micro computed tomography (microCT), and Focused Ion Beam Scanning Electron Microscopy (FIB-SEM) approach for high-resolution correlative three-dimensional imaging to advance our understanding of sperm-female interactions in Drosophila melanogaster. Using this multimodal approach, we were able to scan the lower female reproductive tract and distal portion of the seminal receptacle at low magnification, and to subsequently zoom in for further analysis on an ultrastructural level. Our findings highlight aspects of the way in which the seminal receptacle keeps sperm viable in the lumen, and set the stage for further studies. The methods developed are suitable not only for Drosophila but also for other organisms with soft, delicate tissues.
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Affiliation(s)
- Einat Zelinger
- Department of Entomology, The Hebrew University, Rehovot, Israel
- Center for Scientific Imaging, The Hebrew University, Rehovot, Israel
| | - Vlad Brumfeld
- Chemical Research Support Department, Weizmann Institute, Rehovot, Israel
| | - Katya Rechav
- Chemical Research Support Department, Weizmann Institute, Rehovot, Israel
| | - Daniel Waiger
- Center for Scientific Imaging, The Hebrew University, Rehovot, Israel
| | - Tally Kossovsky
- Center for Scientific Imaging, The Hebrew University, Rehovot, Israel
| | - Yael Heifetz
- Department of Entomology, The Hebrew University, Rehovot, Israel.
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Garlovsky MD, Ahmed-Braimah YH. Evolutionary Quantitative Proteomics of Reproductive Protein Divergence in Drosophila. Mol Cell Proteomics 2023; 22:100610. [PMID: 37391044 PMCID: PMC10407754 DOI: 10.1016/j.mcpro.2023.100610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2022] [Revised: 05/11/2023] [Accepted: 06/04/2023] [Indexed: 07/02/2023] Open
Abstract
Reproductive traits often evolve rapidly between species. Understanding the causes and consequences of this rapid divergence requires characterization of female and male reproductive proteins and their effect on fertilization success. Species in the Drosophila virilis clade exhibit rampant interspecific reproductive incompatibilities, making them ideal for studies on diversification of reproductive proteins and their role in speciation. Importantly, the role of intraejaculate protein abundance and allocation in interspecific divergence is poorly understood. Here, we identify and quantify the transferred male ejaculate proteome using multiplexed isobaric labeling of the lower female reproductive tract before and immediately after mating using three species of the virilis group. We identified over 200 putative male ejaculate proteins, many of which show differential abundance between species, suggesting that males transfer a species-specific allocation of seminal fluid proteins during copulation. We also identified over 2000 female reproductive proteins, which contain female-specific serine-type endopeptidases that showed differential abundance between species and elevated rates of molecular evolution, similar to that of some male seminal fluid proteins. Our findings suggest that reproductive protein divergence can also manifest in terms of species-specific protein abundance patterns.
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Delbare SYN, Jain AM, Clark AG, Wolfner MF. Transcriptional programs are activated and microRNAs are repressed within minutes after mating in the Drosophila melanogaster female reproductive tract. BMC Genomics 2023; 24:356. [PMID: 37370014 PMCID: PMC10294459 DOI: 10.1186/s12864-023-09397-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 05/22/2023] [Indexed: 06/29/2023] Open
Abstract
BACKGROUND The female reproductive tract is exposed directly to the male's ejaculate, making it a hotspot for mating-induced responses. In Drosophila melanogaster, changes in the reproductive tract are essential to optimize fertility. Many changes occur within minutes after mating, but such early timepoints are absent from published RNA-seq studies. We measured transcript abundances using RNA-seq and microRNA-seq of reproductive tracts of unmated and mated females collected at 10-15 min post-mating. We further investigated whether early transcriptome changes in the female reproductive tract are influenced by inhibiting BMPs in secondary cells, a condition that depletes exosomes from the male's ejaculate. RESULTS We identified 327 differentially expressed genes. These were mostly upregulated post-mating and have roles in tissue morphogenesis, wound healing, and metabolism. Differentially abundant microRNAs were mostly downregulated post-mating. We identified 130 predicted targets of these microRNAs among the differentially expressed genes. We saw no detectable effect of BMP inhibition in secondary cells on transcript levels in the female reproductive tract. CONCLUSIONS Our results indicate that mating induces early changes in the female reproductive tract primarily through upregulation of target genes, rather than repression. The upregulation of certain target genes might be mediated by the mating-induced downregulation of microRNAs. Male-derived exosomes and other BMP-dependent products were not uniquely essential for this process. Differentially expressed genes and microRNAs provide candidates that can be further examined for their participation in the earliest alterations of the reproductive tract microenvironment.
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Affiliation(s)
- Sofie Y N Delbare
- Department of Molecular Biology & Genetics, Cornell University, Ithaca, NY, 14853, USA.
| | - Asha M Jain
- Department of Molecular Biology & Genetics, Cornell University, Ithaca, NY, 14853, USA
| | - Andrew G Clark
- Department of Molecular Biology & Genetics, Cornell University, Ithaca, NY, 14853, USA
| | - Mariana F Wolfner
- Department of Molecular Biology & Genetics, Cornell University, Ithaca, NY, 14853, USA
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Chen J, Du X, Xu X, Zhang S, Yao L, He X, Wang Y. Comparative Proteomic Analysis Provides New Insights into the Molecular Basis of Thermal-Induced Parthenogenesis in Silkworm ( Bombyx mori). INSECTS 2023; 14:insects14020134. [PMID: 36835703 PMCID: PMC9962255 DOI: 10.3390/insects14020134] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 01/14/2023] [Accepted: 01/19/2023] [Indexed: 05/27/2023]
Abstract
Artificial parthenogenetic induction via thermal stimuli in silkworm is an important technique that has been used in sericultural production. However, the molecular mechanism underlying it remains largely unknown. We have created a fully parthenogenetic line (PL) with more than 85% occurrence and 80% hatching rate via hot water treatment and genetic selection, while the parent amphigenetic line (AL) has less than 30% pigmentation rate and less than 1% hatching rate when undergoing the same treatment. Here, isobaric tags for relative and absolute quantitation (iTRAQ)-based analysis were used to investigate the key proteins and pathways associated with silkworm parthenogenesis. We uncovered the unique proteomic features of unfertilized eggs in PL. In total, 274 increased abundance proteins and 211 decreased abundance proteins were identified relative to AL before thermal induction. Function analysis displayed an increased level of translation and metabolism in PL. After thermal induction, 97 increased abundance proteins and 187 decreased abundance proteins were identified. An increase in stress response-related proteins and decrease in energy metabolism suggested that PL has a more effective response to buffer the thermal stress than AL. Cell cycle-related proteins, including histones, and spindle-related proteins were decreased in PL, indicating an important role of this decrease in the process of ameiotic parthenogenesis.
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Affiliation(s)
- Jine Chen
- Institute of Sericulture and Tea, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China
| | - Xin Du
- Institute of Sericulture and Tea, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China
| | - Xia Xu
- Institute of Sericulture and Tea, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China
| | - Sheng Zhang
- Proteomics and Metabolomics Facility, Institute of Biotechnology, Cornell University, Ithaca, NY 14853, USA
| | - Lusong Yao
- Institute of Sericulture and Tea, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China
| | - Xiuling He
- Institute of Sericulture and Tea, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China
| | - Yongqiang Wang
- Institute of Sericulture and Tea, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China
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Hakala SM, Fujioka H, Gapp K, De Gasperin O, Genzoni E, Kilner RM, Koene JM, König B, Linksvayer TA, Meurville MP, Negroni MA, Palejowski H, Wigby S, LeBoeuf AC. Socially transferred materials: why and how to study them. Trends Ecol Evol 2022; 38:446-458. [PMID: 36543692 DOI: 10.1016/j.tree.2022.11.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Revised: 11/21/2022] [Accepted: 11/25/2022] [Indexed: 12/23/2022]
Abstract
When biological material is transferred from one individual's body to another, as in ejaculate, eggs, and milk, secondary donor-produced molecules are often transferred along with the main cargo, and influence the physiology and fitness of the receiver. Both social and solitary animals exhibit such social transfers at certain life stages. The secondary, bioactive, and transfer-supporting components in socially transferred materials have evolved convergently to the point where they are used in applications across taxa and type of transfer. The composition of these materials is typically highly dynamic and context dependent, and their components drive the physiological and behavioral evolution of many taxa. Our establishment of the concept of socially transferred materials unifies this multidisciplinary topic and will benefit both theory and applications.
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Han B, Wei Q, Amiri E, Hu H, Meng L, Strand MK, Tarpy DR, Xu S, Li J, Rueppell O. The molecular basis of socially induced egg-size plasticity in honey bees. eLife 2022; 11:80499. [PMID: 36346221 PMCID: PMC9747152 DOI: 10.7554/elife.80499] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Accepted: 11/07/2022] [Indexed: 11/11/2022] Open
Abstract
Reproduction involves the investment of resources into offspring. Although variation in reproductive effort often affects the number of offspring, adjustments of propagule size are also found in numerous species, including the Western honey bee, Apis mellifera. However, the proximate causes of these adjustments are insufficiently understood, especially in oviparous species with complex social organization in which adaptive evolution is shaped by kin selection. Here, we show in a series of experiments that queens predictably and reversibly increase egg size in small colonies and decrease egg size in large colonies, while their ovary size changes in the opposite direction. Additional results suggest that these effects cannot be solely explained by egg-laying rate and are due to the queens' perception of colony size. Egg-size plasticity is associated with quantitative changes of 290 ovarian proteins, most of which relate to energy metabolism, protein transport, and cytoskeleton. Based on functional and network analyses, we further study the small GTPase Rho1 as a candidate regulator of egg size. Spatio-temporal expression analysis via RNAscope and qPCR supports an important role of Rho1 in egg-size determination, and subsequent RNAi-mediated gene knockdown confirmed that Rho1 has a major effect on egg size in honey bees. These results elucidate how the social environment of the honey bee colony may be translated into a specific cellular process to adjust maternal investment into eggs. It remains to be studied how widespread this mechanism is and whether it has consequences for population dynamics and epigenetic influences on offspring phenotype in honey bees and other species.
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Affiliation(s)
- Bin Han
- Institute of Apicultural Research/Key Laboratory of Pollinating Insect Biology, Ministry of Agriculture and Rural Affairs, Chinese Academy of Agricultural Sciences, Beijing, China.,Department of Biology, University of North Carolina Greensboro, Greensboro, United States
| | - Qiaohong Wei
- Institute of Apicultural Research/Key Laboratory of Pollinating Insect Biology, Ministry of Agriculture and Rural Affairs, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Esmaeil Amiri
- Department of Biology, University of North Carolina Greensboro, Greensboro, United States.,Delta Research and Extension Center, Mississippi State University, Stoneville, United States
| | - Han Hu
- Institute of Apicultural Research/Key Laboratory of Pollinating Insect Biology, Ministry of Agriculture and Rural Affairs, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Lifeng Meng
- Institute of Apicultural Research/Key Laboratory of Pollinating Insect Biology, Ministry of Agriculture and Rural Affairs, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Micheline K Strand
- Biological and Biotechnology Sciences Branch, U.S. Army Research Office, DEVCOM-ARL, Baltimore, United States
| | - David R Tarpy
- Department of Applied Ecology, North Carolina State University, Raleigh, Canada
| | - Shufa Xu
- Institute of Apicultural Research/Key Laboratory of Pollinating Insect Biology, Ministry of Agriculture and Rural Affairs, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Jianke Li
- Institute of Apicultural Research/Key Laboratory of Pollinating Insect Biology, Ministry of Agriculture and Rural Affairs, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Olav Rueppell
- Department of Biological Sciences, University of Alberta, Edmonton, Canada
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Wang X, Zhao N, Wang T, Du S, Liu Q, Li J. Transcriptome Analysis Provides Insights into Copulation, Fertilization, and Gestation in Sebastes schlegelii. Genes (Basel) 2022; 13:genes13101812. [PMID: 36292697 PMCID: PMC9601582 DOI: 10.3390/genes13101812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2022] [Revised: 09/26/2022] [Accepted: 09/29/2022] [Indexed: 11/16/2022] Open
Abstract
Among the viviparous marine teleosts of China, the black rockfish (Sebastes schlegelii Hilgendorf) is one of the most economically important. In addition to copulation and internal fertilization, it features lengthy sperm storage in the female ovary as well as a high rate of abortion. A network of gene regulation is necessary for these processes. To elucidate the mechanisms of copulation, fertilization, and gestation, it is essential to determine the genetic basis of viviparous teleost oogenesis and embryogenesis. In this study, we analyzed the transcriptome of the ovary during different developmental phases to investigate the dynamic changes that occur. We constructed 24 ovary transcriptomes. In order to investigate the regulation of embryogenesis, differentially expressed genes (DEGs) with specific expression patterns were subjected to gene ontology annotation, pathway analyses, and weighted gene co-expression network analysis (WGCNA). The up-regulated genes were significantly enriched in focal adhesion, regulation of the actin cytoskeleton, Wnt, and ECM-receptor interaction signaling pathways. As a result of our study, we provide omics evidence for copulation, fertilization, and gestation in viviparous marine teleosts. Decoding the S. schlegelii gene regulation network, as well as providing new insights into embryogenesis, is highly valuable to researchers in the marine teleost reproduction sciences.
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Affiliation(s)
- Xueying Wang
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China
| | - Ning Zhao
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Tao Wang
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China
- Qingdao Agricultural University, Qingdao 266237, China
| | - Shuran Du
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China
- Qingdao Agricultural University, Qingdao 266237, China
| | - Qinghua Liu
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China
| | - Jun Li
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China
- Correspondence: ; Tel./Fax: +86-532-82898718
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Functional Diversity and Evolution of the Drosophila Sperm Proteome. Mol Cell Proteomics 2022; 21:100281. [PMID: 35985624 PMCID: PMC9494239 DOI: 10.1016/j.mcpro.2022.100281] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 07/28/2022] [Accepted: 08/08/2022] [Indexed: 01/18/2023] Open
Abstract
Spermatozoa are central to fertilization and the evolutionary fitness of sexually reproducing organisms. As such, a deeper understanding of sperm proteomes (and associated reproductive tissues) has proven critical to the advancement of the fields of sexual selection and reproductive biology. Due to their extraordinary complexity, proteome depth-of-coverage is dependent on advancements in technology and related bioinformatics, both of which have made significant advancements in the decade since the last Drosophila sperm proteome was published. Here, we provide an updated version of the Drosophila melanogaster sperm proteome (DmSP3) using improved separation and detection methods and an updated genome annotation. Combined with previous versions of the sperm proteome, the DmSP3 contains a total of 3176 proteins, and we provide the first label-free quantitation of the sperm proteome for 2125 proteins. The top 20 most abundant proteins included the structural elements α- and β-tubulins and sperm leucyl-aminopeptidases. Both gene content and protein abundance were significantly reduced on the X chromosome, consistent with prior genomic studies of X chromosome evolution. We identified 9 of the 16 Y-linked proteins, including known testis-specific male fertility factors. We also identified almost one-half of known Drosophila ribosomal proteins in the DmSP3. The role of this subset of ribosomal proteins in sperm is unknown. Surprisingly, our expanded sperm proteome also identified 122 seminal fluid proteins (Sfps), proteins originally identified in the accessory glands. We show that a significant fraction of 'sperm-associated Sfps' are recalcitrant to concentrated salt and detergent treatments, suggesting this subclass of Sfps are expressed in testes and may have additional functions in sperm, per se. Overall, our results add to a growing landscape of both sperm and seminal fluid protein biology and in particular provides quantitative evidence at the protein level for prior findings supporting the meiotic sex-chromosome inactivation model for male-specific gene and X chromosome evolution.
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Abstract
Pheromones exchanged by conspecifics are a major class of chemical signals that can alter behavior, physiology, and development. In particular, males and females communicate with potential mating partners via sex pheromones to promote reproductive success. Physiological and developmental mechanisms by which pheromones facilitate progeny production remain largely enigmatic. Here, we describe how a Caenorhabditis elegans male pheromone, ascr#10, improves the oogenic germline. Before most signs of aging become evident, C. elegans hermaphrodites start producing lower-quality gametes characterized by abnormal morphology, increased rates of chromosomal nondisjunction, and higher penetrance of deleterious alleles. We show that exposure to the male pheromone substantially ameliorates these defects and reduces embryonic lethality. ascr#10 stimulates proliferation of germline precursor cells in adult hermaphrodites. Coupled to the greater precursor supply is increased physiological germline cell death, which is required to improve oocyte quality in older mothers. The hermaphrodite germline is sensitive to the pheromone only during a time window, comparable in duration to a larval stage, in early adulthood. During this period, prereproductive adults assess the suitability of the environment for reproduction. Our results identify developmental events that occur in the oogenic germline in response to a male pheromone. They also suggest that the opposite effects of the pheromone on gamete quality and maternal longevity arise from competition over resource allocation between soma and the germline.
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