We have developed easy methods for generating transgenic animals. We undertake studies of functional genomics using transgenic mice and rats over expressing important genes or animals with inheritable RNAi mediated knockdown of a specific gene. At cellular and systems level, we work to delineate basis of somatic and germ cell differentiation using genomics and proteomics approaches. We are also attempting to generate transgenic farmed animals to produce costly therapeutic proteins in the milk to increase their affordability.
Summary of Research:
Presently used techniques for making transgenic animals are cumbersome and require large number of zygotes from several females that are then killed. This has limited frank use of this technology in the era of human and mouse genome where technology to rapidly identify gene sequences have advanced remarkably, however, there is a great backlog in knowing functions of such large number of genes. Taking this as a challenge, we have developed a death-less technique of transgenesis through in vivo electroporation of genes in dividing spermatogonial stem cells of testis. Such electroporated males rapidly generated transgenic animals (Nature Methods, 2008). We have modified this technique further for mice (Scientific Reports, 2013) and Rats (Molecular Therapy:Neucleic Acid, 2016). These have a worldwide impact because they are easily adaptable and avoid killing of females for obtaining large number of fertilized oocytes. We have initiated projects to create farm animals for generating costly therapeutic proteins of human use in the milk, mainly to make them cheaper and affordable. For this, we have isolated promoter of buffalo beta casein gene and confirmed its functionality (Journal of Biotechnology, 2015). We are working towards generating transgenic animals expressing different therapeutic proteins under this promoter.
Globally, there is a phenomenal rise in male infertility. In addition to genetic causes, there are several environmental and life style related effects leading to compromised fertility. We believe that onset of puberty is associated with the gain of fertility. We have divulged important molecular events leading to attainment of fertility at puberty by functional studies of monkey testicular Sertoli cells (which regulate germ cell differentiation in testis and are called “nurse” cells). Our observations have provided valuable clues for diagnosis and treatment of compromised fertility in males ( J.of Clin. Endo.Metab., 2006 ). This has also helped in determining androgen and FSH signalling defects related to compromised cellular functions within testis which has paved the way for potential circumvention of certain forms of idiopathic infertility in man ( Human Reproduction, 2012; American journal of physiology, 2012; Endocrinology,2015). In addition to this, we have undertaken differential genomics studies of Sertoli cells from spermatogenically active and non-active testes of mice, rat and monkey using DNA microarray and differential display. Recently we have started multi-omics approach by combining transcriptomics (microarray analysis of differentially expressed genes) guided genome wide computational analysis (TRANSFAC) along with quantitative proteomics (SWATH-MS analysis) of differentially expressed proteins in spermatogenically active and inactive testes. Several target genes/factors have been identified which may play crucial role in this complex process and are being screened for their definitive role by generating transgenic rodent models. We have also stepped into defining roles of different microRNAs related to spermatogenic process. We have performed next generation sequencing of microRNAs from spermatogenically active and inactive testes which have revealed a huge list of microRNAs differentially expressed in these two phases. We are working by over expressing the target microRNA or by diminishing its cellular level using SPONGE mediated sequestration approach through generation of transgenic rodent models for identifying their role in spermatogenesis.
Satyapal Arya, Mansi Shukla, Kamal Mandal, Souvik Sensharma, Amandeep Vats, Ayushi Jain, Nirmalya Ganguli, Nilanjana Ganguli, Rajesh Sarkar, Hironmoy Sarkar, Sweety Batra, Neerja Wadhwa, Neetu Dubey, Dharamveer Singh and Birendra N. Roy.
• Fellow, The Lalor Foundation, USA, Southern Illinois Univ. 1989-1990
• Fellow, A.W. Mellon Foundation, USA, University of Pittsburgh, 1991-1994
• Fellow: The National Academy of Sciences, 2009
• Fellow: Indian National Science Academy, 2009
• Fellow: Indian Academy of Sciences, 2013
• Membership of Professional Societies
• Member of the Endocrine Society, USA
• Member, Guha Research Conference (GRC),India
• Member of the Society of Biological Chemists, India
• Member of the Indian Society for Study of Reproduction and Fertility, India
• Labshetwar Award, 2007, Given by the Indian Society for study of Reproduction and fertility.
• Tata Innovation Fellowship, 2011, Given by DBT for application oriented innovative research carried in India.
• National Academy of Science - Reliance Industries Platinum Jubilee award for application oriented innovations in biological sciences-2011.
• Dr. P. Govindarajalu Gold medal oration award of SRBCE, 2012.
• Richard Masillamony Gold medal oration award -2013 given by Indian Society for Veterinary immunology and Biotechnology.
• Dr. T. C. Anandkumar Gold Medal Oration award of Indian society for study of Reproduction and Fertility, Feb., 2014.