Expression of synaptonemal complex protein 3 [SYCP3] m RNAin the testis: a molecular marker for spermatogenesis in azoospermic men

Men with unexplained infertility and azoospermia are often observed in the context of genetic defects. The expression of a wide variety of genes is developmentally regulated during human meiosis. Synaptonemal Protein 3 [SYCP3] gene, located on chromosome 12, encodes a DNA-binding protein as the structural component of the synaptonemal complex,which mediates the synopsis or homologous pairing of chromosomes during meiosis. Absence of SYCP3 in mice may lead to male infertility as well as female sub-fertility. SYCP3 expression analysis could be a tool for the prediction of human spermatogenesis progression, especially in infertile men. SYCP3 mRNA expression in testicular samples of 110 patients with non-obstructive azoospermia were studied in Avesina Infertility Clinic in Tehran, Iran during 2005 and early 2006. Semi-quantitative nested reverse transcriptase-PCR was employed in order to find the strength of gene expression. Using histopathological scoring for all samples, the expression level of SYCP3 during spermatogenesis was also evaluated. Testicular SYCP3 mRNA expression was observed in 67 patients [60.9%]. The expression level correlated with the degree of spermatogenic failure [p<0.0001]. While this gene had been expressed in patients with hypo-spermatogenesis and maturation arrest, a lack of expression was seen in those with spermatogonial arrest, Sertoli cell-only syndrome and testicular atrophy. These data indicate that SYCP3 is expressed in the human testis and it is restricted to germ cells. Our findings, in association with those obtained in experimental animals, show that lack of SYCP3 expression may have negative effects on spermatogenesis and male fertility. SYCP3 gene expression may help detect specific spermatogenesis stages in conjunction with histopathological findings

[Extraction and purification of ferritin from liver tissue]

Ferritin with molecular weight of 450 kDa is the most important iron storage protein and is made of 24 subunits consisting of light and heavy chains. Each ferritin molecule is able to store 4500 Fe[3+] molecules. The aim of this study was to determine the preparation of highly pure ferritin for usage in diagnostic and research systems. In this study, ferritin was extracted and purified by homogenizing liver tissue, heating at 75 degrees centigrade, ammonium sulfate fractionation and gel filtration chromatography on sephadex G-200 column. The purify of ferritin was improved by using recycling chromatography. Resulted protein was electrophoresed on polyacrylamide gel in the presence of sodium dodecylsulfate [SDS-PAGE]. Existence of ferritin was confirmed by ELISA test and potassium ferricyanide staining of gel. Silver nitrate staining of gel was used to confirm the purity of ferritin. Electrophoresis of ferritin under reducing conditions in presence of 2- mercapto ethanol was done to show the subunits [19 and 21 kDa] of ferritin. This purification method resulted in very pure ferritin and the yield was 100 microg/gr of wet liver tissue. Electrophoresis of ferritin under reducing conditions in presence of 2- mercapto ethanol showed the both subunits [19 and 21 kDa] of ferritin. Highly pure ferritin resulted by this method is appropriate for diagnostic and research purpose and the yield is reasonable comparing other studies