Identification of mouse trp homologs and lipid rafts from spermatogenic cells and sperm

FEBS Letters

Darszon, Alberto¹  Felix, Ricardo²  Serrano, Carmen J.¹  Treviño, Claudia L.¹  Beltrán, Carmen¹ 

[1] Department of Genetics and Molecular Physiology, Institute of Biotechnology, UNAM, Avenida Universidad 2001, Col. Chamilpa, CP 62100, Cuernavaca, Mor., Mexico;Department of Physiology, Biophysics and Neuroscience, Cinvestav-IPN, Mexico City, Mexico

关键词: Ca2+ channel;    trp;    Caveolin;    Lipid raft;    Sperm;    Spermatogenic cell;   

DOI  :  10.1016/S0014-5793(01)03134-9

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Intracellular Ca²⁺ has an important regulatory role in the control of sperm motility, capacitation, and the acrosome reaction (AR). However, little is known about the molecular identity of the membrane systems that regulate Ca²⁺ in sperm. In this report, we provide evidence for the expression of seven Drosophila transient receptor potential homolog genes (trp1–7) and three of their protein products (Trp1, Trp3 and Trp6) in mouse sperm. Allegedly some trps encode capacitative Ca²⁺ channels. Immunoconfocal images showed that while Trp6 was present in the postacrosomal region and could be involved in sperm AR, expression of Trp1 and Trp3 was confined to the flagellum, suggesting that they may serve sperm to regulate important Ca²⁺-dependent events in addition to the AR. Likewise, one of these proteins (Trp1) co-immunolocalized with caveolin-1, a major component of caveolae, a subset of lipid rafts potentially important for signaling events and Ca²⁺ flux. Furthermore, by using fluorescein-coupled cholera toxin B subunit, which specifically binds to the raft component ganglioside GM1, we identified caveolin- and Trp-independent lipid rafts residing in the plasma membrane of mature sperm. Notably, the distribution of GM1 changes drastically upon completion of the AR.

【 授权许可】

Unknown