melanogaster and, more recently, Drosophila simulans.

Previous studies on the identification of Drosophila accessory gland products have largely focused on characterisation of male-specific accessory gland cDNAs from D. Many of these proteins are synthesised by the male accessory glands and are secreted into the accessory gland lumen, where they are stored until required. In Drosophila melanogaster, the male seminal fluid contains proteins that are important for reproductive success. Walker, Michael J Rylett, Caroline M Keen, Jeff N Audsley, Neil Sajid, Mohammed Shirras, Alan D Isaac, R Elwyn Proteomic identification of Drosophila melanogaster male accessory gland proteins, including a pro-cathepsin and a soluble gamma-glutamyl transpeptidase. Conclusion We have applied biochemical approaches, not used The strong Î³-glutamyl transpeptidase activity found in the secretions provides an explanation for the observation that glutamic acid is the most abundant free amino acid in accessory gland secretions of D. GGT-1 is possibly involved in maintaining a protective redox environment for sperm. Î³-Glutamyl transpeptidases are type II integral membrane proteins however, the identified AG Î³-glutamyl transpeptidase (GGT-1 is unusual in that it is predicted to be a soluble secreted protein, a prediction that is supported by biochemical evidence. This peptidase may have a role in the processing of female and other male-derived proteins, but is unlikely to be involved in the processing of the sex peptide. Enzymatic studies established that accessory gland secretions contain a cysteine peptidase zymogen that can be activated at low pH. They included protein-folding and stress-response proteins, a hormone, a lipase, a serpin, a cysteine-rich protein and two peptidases, a pro-enzyme form of a cathepsin K-like cysteine peptidase and a Î³-glutamyl transpeptidase. Results Thirteen secreted accessory gland proteins, including seven new accessory gland proteins, were identified by 2D-gel electrophoresis combined with mass spectrometry of tryptic fragments. In the present study, we have used a proteomics approach without any sex bias to identify proteins in D.

Proteomic identification of Drosophila melanogaster male accessory gland proteins, including a pro-cathepsin and a soluble Î³-glutamyl transpeptidaseįull Text Available Background In Drosophila melanogaster, the male seminal fluid contains proteins that are important for reproductive success. Particularly, the specific response in the testis suggests that this tissue is ideal for the detection of illicit androgen administration in veal calves and beef cattle. The confirmation of the regulation of RGN gene expression through sex steroid hormones might facilitate the potential detection of hormone abuse in bovine husbandry. In addition, estrogen administration down-regulated RGN gene expression in the accessory sex glands of veal calves and beef cattle, while androgen treatment reduced RGN gene expression only in the testis. Herein, we used quantitative PCR, western blot and immunohistochemistry analyses to demonstrate RGN mRNA and protein expression in bovine tissues. The screening of the regulation and function of anabolic sex steroids via modified gene expression levels in various tissues represents a new approach for the detection of illicit drug treatments. Sex steroid hormones are still illegally used in bovine husbandry to increase muscle mass. Moreover, we investigated whether RGN expression is controlled through sex steroid hormones in bovine target tissues, namely the bulbo-urethral and prostate glands and the testis. Thus, in the present study, we examined RGN mRNA and protein expression in the different tissues and organs of veal calves and beef cattle. Recently, RGN has been identified as a target gene for sex steroid hormones in the prostate glands and testis of rats and humans, but no studies have focused on RGN expression in bovine tissues. Regucalcin expression in bovine tissues and its regulation by sex steroid hormones in accessory sex glands.ĭirectory of Open Access Journals (Sweden)įull Text Available Regucalcin (RGN is a mammalian Ca2+-binding protein that plays an important role in intracellular Ca2+ homeostasis.

Siberian mouse mm27 nude