Puttaswamy Manjunath
Biochimie et spermatozoïdes
Profile
Research expertise
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 (knock-out mouse) may have an effect on fertility and whether this protein could be a cause of infertility or subfertility 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 egg yolk and milk: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 for commercial application.Affiliations and responsabilities
Research affiliations
Research units
Membre
Affiliated institutions
- CIUSSS de l'Est-de-l'Île-de-Montréal – Hôpital Maisonneuve-Rosemont (HMR)
Teaching and supervision
Student supervision
Theses and dissertation supervision (Papyrus Institutional Repository)
A novel purification method for binder of SPerm proteins and characterization of the protein interaction network of BSPH1
Cycle : Doctoral
Grade : Ph. D.
Knockout mouse model generated by CRISPR technology to study the function of BSP proteins on male fertility in vivo
Cycle : Doctoral
Grade : Ph. D.
Binder of SPerm protein interference in sperm-egg interaction
Cycle : Master's
Grade : M. Sc.
Rôle de protéines épididymaires humaines et murines dans les fonctions spermatiques
Cycle : Doctoral
Grade : Ph. D.
Fonction de la protéine Ceroid lipofuscinosis neuronal 5 (CLN5) dans le tri et le recyclage à l’endosome
Cycle : Doctoral
Grade : Ph. D.
Le cancer épithélial des ovaires à cellules claires et de type mucineux exprime un niveau élevé de HYAL-1 : corrélation inverse avec l’expression des récepteurs d’estrogène et de progestérone
Cycle : Master's
Grade : M. Sc.
Étude du mécanisme de protection des spermatozoïdes de mammifères par le lait
Cycle : Doctoral
Grade : Ph. D.
Les gènes et protéines BSP chez la souris et l’humain : clonage, caractérisation, expression sous forme recombinante et étude des fonctions biologiques
Cycle : Doctoral
Grade : Ph. D.
Association des protéines du liquide séminal bovin aux membranes lipidiques par titrage calorimétrique isotherme, microscopie de fluorescence et la technique des monocouches
Cycle : Master's
Grade : M. Sc.
Protéines du liquide séminal bovin et membranes lipidiques modèles : étude des interactions par titrage calorimétrique isotherme et spectroscopie infrarouge
Cycle : Master's
Grade : M. Sc.
Induction de la capacitation des spermatozoïdes épididymaires porcins par pB1 et BSP-A1/-A2, des protéines de la famille des protéines BSP
Cycle : Master's
Grade : M. Sc.
Étude du mécanisme impliqué dans la protection des spermatozoïdes de mammifères par le jaune d'oeuf
Cycle : Doctoral
Grade : Ph. D.
Isolement de protéines liant les phospholipides à partir de tissus et du sérum bovins : évidences pour l'implication dans le transport inverse du cholestérol
Cycle : Master's
Grade : M. Sc.
Caractérisation des protéines AQN-1 ET pB1 du plasma séminal porcin et leur rôle dans la capacitation des spermatozoïdes
Cycle : Master's
Grade : M. Sc.
Isolement de protéines apparentées aux protéines majeures du plasma séminal bovin chez divers mammifères
Cycle : Master's
Grade : M. Sc.
Étude de la capacitation des spermatozoïdes épididymaires bovins en présence des protéines majeures du plasma séminal bovin et des facteurs capacitants
Cycle : Doctoral
Grade : Ph. D.
Clonage et distribution tissulaire des protéines majeures du plasma séminal bovin
Cycle : Master's
Grade : M. Sc.
Le rôle d'une famille de protéines du plasma séminal bovin dans le transport lipidique et la capacitation du spermatozoïde
Cycle : Doctoral
Grade : Ph. D.
Isolation et caractérisation de l'acétylhydrolase du facteur activateur de plaquettes du plasma séminal bovin
Cycle : Doctoral
Grade : Ph. D.
L'héparine et les lipoprotéines de haute densité induisent la capacitation des spermatozoïdes par des mécanismes différents
Cycle : Master's
Grade : M. Sc.
Caractérisation des protéines majeures du plasma séminal bovin et leur rôle dans les fonctions spermatiques
Cycle : Doctoral
Grade : Ph. D.
Interaction des protéines majeures du plasma séminal bovin avec l'héparine et la calmoduline
Cycle : Master's
Grade : M. Sc.
Les protéines majeures du plasma séminal bovin : distribution dans différents tissus et chez diverses espèces et localisation à la surface du spermatozoïde
Cycle : Master's
Grade : M. Sc.
Projects
Research projects
Réseau Québecois en Reproduction (RQR)
Mechanism of mammalian sperm protection by extender components and development of novel extenders free of products of animal origin
BINDER OF SPERM (BSP) GENES AND PROTEINS : ROLE OF HUMAN AND MOUSE BSP PROTEINS IN SPERM FUNCTION AND FERTILIZATION
A microcalorimetry system to define the biochemical parameters of molecular interactions
Mechanism of mammalian sperm protection by extender components and development of novel extenders free of products of animal origin
MAMMALIAN SPERM PRESERVATION : MECHANISM SPERM PROTECTION BY MILK AND DEVELOPMENT OF NOVEL EXTENDERS
DILUTERS OR EXTENDERS FOR MAMMALIAN SPERM PROCESSING AND PRESERVATION
MAMMALIAN SPERM PRESERVATION: MECHANISM SPERM PROTECTION BY MILK AND DEVELOPMENT OF NOVEL EXTENDERS
INSIGHTS INTO THE MECHANISMS UNDERLYING FERTILITY: ROLE OF NOVEL PHOSPHOLIPID-BINDING PROTEINS IN SPERM FUNCTION
Disciplines
- Biochemistry
Areas of expertise
- Nucleic Acids
- Cell
- Chromosome (Living Organisms)
- Enzymes and Proteins
- Gene (Living Organisms)
- Biological and Biochemical Mechanisms
- Bioactive Molecules