Factors which influence sperm ability to fertilize

Department of Cellular and Developmental Biology, University of Palermo, Italy.
Journal of submicroscopic cytology and pathology 09/2005; 37(2):215-22.
Source: PubMed


Different factors influence animal sperm ability to fertilize. Some of them are reviewed here, sperm motility, block to polyspermy, chemioattraction, sperm competition for fertilization. Old and new data are reported, as for example the new notions on sperm motility derived from site directed mutagenesis in rodents, the new notions on the odour receptors in mammalian sperm attraction and new notions on sperm competition, which is variable in different species.

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    • "Mammalian sperm acquire their capability for motility as they traverse the epididymis. Thus, sperm motility is a key factor in allowing us to determine semen quality and fertilizing capacity (Geraci and Giudice, 2005; Petrunkina et al., 2005; Jaffe et al., 2006). Motility in semen is widely controlled by a variety of factors, including concentrations of surrounding metabolites and ions (Ca 2þ , Mg 2þ , etc.), pH, and temperature (Vijayaraghavan et al., 1994; Irvine, 1997; Vera et al., 2003; Myers et al., 2004; Alavi and Cosson, 2005; Pal et al., 2006; Parker and McDaniel, 2006). "
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    ABSTRACT: Zinc alpha 2-glycoprotein (ZAG) is a protein of interest because of its ability to play many important functions in the human body, including fertilization and lipid mobilization. After the discovery of this molecule, during the last 5 decades, various studies have been documented on its structure and functions, but still, it is considered as a protein with an unknown function. Its expression is regulated by glucocorticoids. Due to its high sequence homology with lipid-mobilizing factor and high expression in cancer cachexia, it is considered as a novel adipokine. On the other hand, structural organization and fold is similar to MHC class I antigen-presenting molecule; hence, ZAG may have a role in the expression of the immune response. The function of ZAG under physiologic and cancerous conditions remains mysterious but is considered as a tumor biomarker for various carcinomas. There are several unrelated functions that are attributed to ZAG, such as RNase activity, regulation of melanin production, hindering tumor proliferation, and transport of nephritic by-products. This article deals with the discussion of the major aspects of ZAG from its gene structure to function and metabolism.
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