Calpain 11 is unique to mouse spermatogenic cells

Abstract

The calpains are a family of calcium-dependent thiol proteases involved in intracellular processing of proteins. They occur as heterodimers containing one of various large subunits and a common small subunit. Some of the large subunits are expressed ubiquitously and others are expressed in a restricted set of tissues. We have cloned the cDNA for mouse calpain 11 and demonstrated that it is expressed specifically in the mouse testis. The mRNA begins to accumulate in the testis between days 14 and 16 after birth, corresponding to the period of pachytene spermatocyte development. The protein is detected by day 18 after birth, during mid to late pachytene spermatocyte development, and is present in the acrosomal region of spermatozoa from the cauda epididymis. The expression of calpain 11 during spermatogenesis and its localization in spermatozoa suggest that it is involved in regulating calcium-dependent signal transduction events during meiosis and sperm functional processes.

Calpain modulates capacitation and acrosome reaction through cleavage of the spectrin cytoskeleton

“…Finally, our data indicate that the activity of calpain is specific; it does not alter the actin cytoskeleton or other cytoskeletal proteins such as utrophin and filamin-1, although as in other cells, calpain might have other non-cytoskeletal substrates associated with PM such as Ca 2C channels or receptors (Sandoval et al 2006, Croall & Ersfeld 2007. On the other hand, although our data suggest that calpain-1 could be one of the calpains involved in spectrin cleavage and AR, we do not discard the possibility that other calpain may be implicated in such processes, since the calpain inhibitors are not specific for calpain-1, and calpain-11 has been reported in mammalian sperm (Ben-Aharon et al 2006). Different and important membrane domains are established in both the acrosome and flagella of mammalian sperm, which display distinct biochemical and physiological functions; however, little is known Calpain cleaves spectrin during capacitation about the role of the cytoskeleton in the establishment of these membrane domains.…”

Genome engineering uncovers 54 evolutionarily conserved and testis-enriched genes that are not required for male fertility in mice

“…We identified 4 genes from published reports, and we identified an additional 50 genes from the bioinformatic predictions. The genes identified from the published reports are Capn11, Lyzl4, Pkdrej, and 1110017D15Rik (16)(17)(18)(19). The genes identified from our bioinformatic predictions include genes with nomenclature based on sequencing at RIKEN (e.g., 1700007G11Rik, 1700019B03Rik, 1700034J05Rik, 1700125H20Rik, 1700015F17Rik, 2900092C05Rik, 4930522H14Rik, 1700011E24Rik, and 4933417A18Rik), based on domains (e.g., Ccdc178, Efcab3, Ms4a13, Smim23, and Tmem247), or based on groupings within conserved families (e.g., Syngr4, Ube2e, and Fam217a).…”

“…For our initial studies, we picked 16 genes (1700093K21Rik, Adam18, Capn11, Efcab3, Lrrc36, Lyzl4, Lyzl6, Pkdrej, Spaca3, Spata4, Spata9, Syngr4, Tepp, Tex22, Tsga13, and Zcchc13) that were predominantly expressed in testis based on previous reports [Capn11 (16), Lyzl4 (19), Pkdrej (17)] or analysis of the UniGene EST database. To confirm that the candidate genes were expressed in testis, we performed RT-PCR for each gene using testicular cDNAs obtained from 1-, 2-, 3-, 4-, and 5-wk-old mice.…”

Three Testis-Specific Paralogous Serine Proteases Play Different Roles in Murine Spermatogenesis and Are Involved in Germ Cell Survival During Meiosis1

“…However, it is evident that proteases have important functions in meiosis because mice that lack some protease inhibitors exhibit impaired meiosis [22,23]. In addition, several proteases are expressed in spermatocytes [24][25][26][27]. Therefore, the functions of protease in germ cells during meiosis need to be elucidated.…”