Microinjection of foreign DNA in male pronucleus by in-vitro embryo manipulation is difficult but remains the method of choice for generating transgenic animals. Other procedures, including retroviral and embryonic stem cell mediated transgenesis are equally complicated and have limitations. Although our previously reported technique of testicular transgenesis circumvented several limitations, it involved many steps, including surgery and hemicastration, which carried risk of infection and impotency. We improved this technique further, into a two step non-surgical electroporation procedure, for making transgenic mice. In this approach, transgene was delivered inside both testes by injection and modified parameters of electroporation were used for in-vivo gene integration in germ cells. Using variety of constructs, germ cell integration of the gene and its transmission in progeny was confirmed by PCR, slot blot and immunohistochemical analysis. This improved technique is efficient, requires substantially less time and can be easily adopted by various biomedical researchers.

Some reptiles are known to possess sperm storage in the female genital tract. Examination of the oviduct of the lizard Calotes versicolor shows the presence of sperm in storage pockets of the uterovaginal region throughout the reproductive cycle. Histochemical studies indicate that the epithelium of these pockets resembles the local oviductal epithelium and that a considerable amount of activity of steroidogenic and metabolic enzymes exists.

FSH acts via testicular Sertoli cells (Sc) bearing FSH receptor (FSH-R) for regulating male fertility. Despite an adult-like FSH milieu in infant boys and monkeys, spermatogenesis is not initiated until the onset of puberty. We used infant and pubertal monkey Sc to reveal the molecular basis underlying developmental differences of FSH-R signaling in them. Unlike pubertal Sc, increasing doses of FSH failed to augment cAMP production by infant Sc. The expression of Gαs subunit and Ric8b, which collectively activate adenylyl cyclase (AC) for augmenting cAMP production and gene transcription, were significantly low in infant Sc. However, forskolin, which acts directly on AC bypassing FSH-R, augmented cAMP production and gene transcription uniformly in both infant and pubertal Sc. FSH-induced Gαs mRNA expression was higher in pubertal Sc. However, Gαi-2 expression was down-regulated by FSH in pubertal Sc, unlike infant Sc. FSH failed, but forskolin or 8-Bromoadenosine 3',5'-cyclic monophosphate treatment to infant Sc significantly augmented the expression of transferrin, androgen binding protein, inhibin-β-B, stem cell factor, and glial-derived neurotropic factor, which are usually up-regulated by FSH in pubertal Sc during spermatogenic onset. This suggested that lack of FSH mediated down-regulation of Gαi-2 expression and limited expression of Gαs subunit as well as Ric8b may underlie limited FSH responsiveness of Sc during infancy. This study also divulged that intracellular signaling events downstream of FSH-R are in place and can be activated exogenously in infant Sc. Additionally, this information may help in the proper diagnosis and treatment of infertile individuals having abnormal G protein-coupled FSH-R.

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