Puttaswamy Manjunath, Ph.D.

Professor Université de Montréal

Department of medecine

Centre de recherche

Hôpital Maisonneuve-Rosemont

5415 L'Assomption

Montréal, Qc., Canada, H1T 2M4

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Tel: 514-252-3562

Fax: 514-252-3430

Research Interests: 

  • Biochemical characterization and physiological role of proteins from the male genital tract
  • Mechanism of sperm protection by extender components and development novel extenders free of products of biological origin

Summary of Results:

Biochemical characterization and physiological role(s) of proteins from the male reproductive tract:

In mammals, sperm emerging from the male reproductive tract are incapable of fertilizing egg; however, they acquire this ability during their journey in the female reproductive tract. This prerequisite conditioning is called capacitation and it is one of the key events that regulate fertility. A part of this process involves loss or modification of surface components acquired by sperm during epididymal maturation and their contact with seminal plasma. We have isolated and characterized a family of proteins from bovine seminal plasma (BSP), which are added to sperm during ejaculation. Our studies have demonstrated that these proteins are essential for capacitation and are ubiquitous in mammals. Sequences homologous to BSP proteins have been identified in human and mouse genomes. Two homologous cDNA sequences in mouse and one in human have been cloned and their specific expression (mRNA) in epididymis has been shown. To study the functions, mouse and human BSP homologous proteins have been expressed in bacteria and purified. It has been shown that these proteins have several binding characteristics in common with their homologs previously studied and may also promote sperm capacitation. We are now interested in whether the deletion of these proteins in mouse (CRISPR/Cas9 gene-editing technique) may have an effect on fertility and whether defect in this protein could be a cause of infertility in men. These studies may lead to a better understanding of the mechanisms involved in fertilization and identification of an important factor for human fertility.

Mechanism of sperm protection by extender components and development novel extenders free of products of biological origin:

Over the past 70 years, egg-yolk and milk have been routinely used in both liquid semen extenders and those used to cryopreserve sperm. However, the mechanism by which egg yolk and milk protect sperm during liquid storage or from freezing damage is unknown. Thus, our laboratory is studying the mechanisms involved in sperm protection by milk and egg yolk. We discovered that a group of phospholipid-binding proteins (PL-BP), which are detrimental to sperm, are added to sperm at ejaculation. Interestingly, these detrimental factors bind caseins/whey proteins and low-density lipoproteins found in milk and egg yolk respectively. This interaction appears to reduce lipid loss from the sperm membrane, thereby preventing membrane damage during storage and preserving the sperm functions (motility, viability and acrosomal integrity). In future studies we would like to further characterize the interaction between PL-BPs and milk/egg yolk components and develop novel sperm storage medium free of biological products for commercial application.

 Lab members: 



Email address

Bruno Prud'homme

Research assistant

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Marzieh Eskandari Shahraki 

PhD student 

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Samin Sabouhi Zarafshan

PhD student

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Abdullah Alnoman

MSc student

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Hamed Vala

MSc student

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List of publications (since 2006):

Plante G, Prud'homme B, Fan J, Lafleur M, Manjunath P. (2016) Evolution and function of mammalian binder of sperm proteins. Cell Tissue Res. 363(1):105-27.

Plante G, Lusignan MF, Lafleur M, Manjunath P. (2015) Interaction of milk proteins and Binder of Sperm (BSP) proteins from boar, stallion and ram semen. Reprod Biol Endocrinol. 15;13:92.

Plante G, Manjunath P. (2015) Epididymal Binder of SPerm genes and proteins: what do we know a decade later? Andrology. 3(5):817-24.

Jois PS, Plante G, Thérien I, Manjunath P. (2015) Functional characterization of the domains of the bovine binder of SPerm 5 (BSP5) protein. Reprod Biol Endocrinol. 19;13:64.

Plante G, Manjunath P. (2015) Murine binder of sperm protein homolog 1: a new player in HDL-induced capacitation. Reproduction. 149(4):367-76.

Plante G, Manjunath P. (2014) Binder of SPerm (BSP) Proteins in the Male Reproductive Tract of Farm Animals. Proceedings, Association for Applied Animal Andrology, 9th Biennial Conference. pages 103-118.

Plante G, Thérien I, Lachance C, Leclerc P, Fan J, Manjunath P. (2014) Implication of the human Binder of SPerm Homolog 1 (BSPH1) protein in capacitation. Mol Hum Reprod. 20(5):409-21.

Plante G, Fan J, Manjunath P. (2014) Murine Binder of SPerm homolog 2 (BSPH2): the black sheep of the BSP superfamily. Biol Reprod. 30;90(1):20.

Therrien A, Manjunath P, Lafleur M. (2013) Chemical and physical requirements for lipid extraction by bovine binder of sperm BSP1. Biochim Biophys Acta. 1828(2):543-51.

Plante G, Thérien I, Manjunath P. (2012) Characterization of recombinant murine binder of sperm protein homolog 1 and its role in capacitation. Biol Reprod. 87(1):20, 1-11.

Lusignan MF, Bergeron A, Lafleur, M, Manjunath, P. (2011) The Major Proteins of Bovine Seminal Plasma Interact with Caseins and Whey Proteins of Milk Extender. Biol Reprod. 85(3):457-64.

Lusignan MF, Manjunath P, Lafleur M. (2011) Thermodynamics of the interaction between bovine Binder of SPerm BSP1 and low-density lipoprotein from hen’s egg yolk. Thermochim Acta. 516, 88-90.

Jois PS, Manjunath P. (2010) The N-terminal part of Binder of sperm 5 (BSP5), which promotes sperm capacitation in bovine species is intrinsically disordered. Biochem Biophys Res Commun. 394(4):1036-41.

Lafleur M, Courtemanche L, Karlsson G, Edwards K, Schwartz JL, Manjunath P. (2010) Bovine binder-of-sperm protein BSP1 promotes protrusion and nanotube formation from liposomes. Biochem Biophys Res Commun. 399(3):406-11.

Lefebvre J, Boileau G, Manjunath P. (2009) Recombinant expression and affinity purification of a novel epididymal human sperm-binding protein BSPH1. Mol. Human Reprod. 15(2):105-14.

Manjunath P, Lefebvre J, Jois PS, Fan J, Wright MW. (2009) New nomenclature for mammalian BSP genes. Biol. Reprod. 80(3):394-7.

Lassiseraye D, Courtemanche L, Bergeron A, Manjunath P, Lafleur M. (2008) Binding of bovine seminal plasma protein BSP-A1/A2 to model membranes: Lipid specificity and Effect of the temperature. Biochim. Biophys. Acta. 1778(2):502-13.

Manjunath P, Lusignan MF, Bergeron A. (2008) Sperm protection by extender components. Proceedings of the Satellite Meeting of 16th International Congress on Animal Reproduction and 6th Biannual Meeting of Association for Applied Animal Andrology. pages 52-63.

Bergeron A, Brindle Y, Blondin P, Manjunath P. (2007) Milk caseins decrease the binding of the major bovine seminal plasma proteins to sperm and prevent lipid loss from the sperm membrane during sperm storage. Biol. Reprod. 77(1):120-6.

Lefebvre J, Fan J, Chevalier S, Sullivan R, Carmona E, Manjunath P. (2007) Genomic structure and tissue-specific expression of human and mouse genes encoding homologs of the major bovine seminal plasma proteins. Mol. Human Reprod. 13(1):45-53.

Lusignan MF, Bergeron A, Crête MH, Lazure C, Manjunath P. (2007) Induction of epididymal boar sperm capacitation by pB1 and BSP-A1/-A2 proteins, members of the BSP protein family. Biol. Reprod. 76(3):424-32.

Manjunath P, Bergeron A, Lefebvre J, Fan J. (2007) Seminal plasma proteins: functions and interaction with protective agents during semen preservation. Soc Reprod Fertil Suppl. 65: 217-228.

Tannert A, Kurz A, Erlemann KR, Müller K, Herrmann A, Schiller J, Töpfer-Petersen E, Manjunath P, Müller P. (2007) The bovine seminal plasma protein PDC-109 extracts phosphorylcholine-containing lipids from the outer membrane leaflet. Eur Biophys J. 36(4-5):461-75.

Bergeron A, Manjunath P. (2006) New insights towards understanding the mechanisms of sperm protection by egg yolk and milk. Mol. Reprod. Dev. 73(10):1338-44.

Fan J, Lefebvre J, Manjunath P. (2006) Bovine seminal plasma proteins and their relatives: a new expanding superfamily in mammals. Gene. 375:63-74.

Gwathmey TM, Ignotz GG, Mueller JL, Manjunath P, Suarez SS. (2006) Bovine seminal plasma proteins PDC-109, BSP-A3 and BSP-30-kDa share functional roles in storing sperm in the oviduct. Biol. Reprod. 75(4):501-7.

Other information:

Patent: Extenders for mammalian sperm processing and preservation. PCT/CA2011/000559 (2010-05-15)