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The mammalian spermatozoon has many cellular compartments, such as head and tail, permitting it to interact with the female reproductive tract and fertilize the egg. It acquires this fertilizing potential during transit through the epididymis, which secretes proteins that coat different sperm domains. Optimal levels of these proteins provide the spermatozoon with its ability to move to, bind to, fuse with, and penetrate the egg; otherwise male infertility results. As few human epididymal proteins have been characterized, this work was performed to generate a database of human epididymal sperm-located proteins involved in maturation. Two-dimensional gel electrophoresis of epididymal tissue and luminal fluid proteins, followed by identification using MALDI-TOF/MS or MALDI-TOF/TOF, revealed over a thousand spots in gels comprising 745 abundant nonstructural proteins, 408 in luminal fluids, of which 207 were present on spermatozoa. Antibodies raised to 619 recombinant or synthetic peptides, used in Western blots, histological sections, and washed sperm preparations to confirm antibody quality and protein expression, indicated their regional location in the epididymal epithelium and highly specific locations on washed functional spermatozoa. Sperm function tests suggested the role of some proteins in motility and protection against oxidative attack. A large database of these proteins, characterized by size, pI, chromosomal location, and function, was given a unified terminology reflecting their sperm domain location. These novel, secreted human epididymal proteins are potential targets for a posttesticular contraceptive acting to provide rapid, reversible, functional sterility in men and they are also biomarkers that could be used in noninvasive assessments of male fertility. Molecular & Cellular Proteomics 9:2517-2528, 2010.There are two major challenges for population and reproductive health. First, rapid global population expansion, which will see the world population reach 9 billion by 2045 (http:// www.census.gov/ipc/www/idb/worldpopgraph.php). Second, infertility is suffered by around 180 million couples, comprising about 10%-15% worldwide and over 25% in some countries, of which 40%-50% is related to the male (http://www.who.int/ reproductivehealth/publications/infertility/progress_63/en/ index.html). Natural fertilization requires tightly coordinated and sequential sperm functions (1), from maturation in the epididymis (2) and survival in the female tract to fusion with the ovum (3). Fertility and infertility are both sides of the same reproductive coin so that understanding one can provide clues to the other. On the one hand, the widespread application to infertile couples of artificial reproductive technology, which bypasses natural fertilization mechanisms, has diverted attention from understanding the biological causes of the infertility for its cure, to that of overcoming the symptom of childlessness. On the other, controlling population growth by contraceptive means is currently only available to large ...

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BackgroundGeographical isolation combined with historical climatic fluctuations have been identified as two major factors that contribute to the formation of new species. On the other hand, biotic factors such as competition and predation are also able to drive the evolution and diversification of organisms. To determine whether geographical barriers contributed to population divergence or speciation in the rare endemic cicada Subpsaltria yangi the population differentiation, genetic structure and phylogeography of the species were investigated in the Loess Plateau and adjacent areas of northwestern China by analysing mitochondrial and nuclear DNA and comparing the calling song structure of 161 male individuals.ResultsThe results reveal a low level of genetic differentiation and relatively simple phylogeographic structure for this species, but two independent clades corresponding to geographically isolated populations were recognised. Genetic and geographical distances were significantly correlated among lineages. Results of divergence-time estimation are consistent with a scenario of isolation due to glacial refugia and interglacial climate oscillation in northwestern China. Significant genetic divergence was found between the population occurring in the Helan Mountains and other populations, and recent population expansion has occurred in the Helan Mountains and/or adjacent areas. This population is also significantly different in calling song structure from other populations.ConclusionsGeographical barriers (i.e., the deserts and semi-deserts surrounding the Helan Mountains), possibly coupled with related ecological differences, may have driven population divergence and allopatric speciation. This provides a possible example of incipient speciation in Cicadidae, improves understanding of population differentiation, acoustic signal diversification and phylogeographic relationships of this rare cicada species of conservation concern, and informs future studies on population differentiation, speciation and phylogeography of other insects with a high degree of endemism in the Helan Mountains and adjacent areas.Electronic supplementary materialThe online version of this article (10.1186/s12862-018-1317-8) contains supplementary material, which is available to authorized users.

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