High impact information on Crisp2

• The cysteine-rich secretory protein domain of Tpx-1 is related to ion channel toxins and regulates ryanodine receptor Ca2+ signaling [1].
• These data show that the Tpx-1 Crisp domain on its own can regulate ion channel activity and provide compelling evidence for a role for Tpx-1 in the regulation of Ca(2+) fluxes observed during sperm capacitation [1].
• Furthermore, the Tpx-1 Crisp domain activated both RyR forms at negative bilayer potentials and showed no effect at positive bilayer potentials when added to the luminal domain of the receptor [1].
• DNA sequencing revealed a complete identity with the hitherto characterized epididymal CRISP-1, testicular CRISP-2, and salivary gland CRISP-3 [2].
• RT-PCR analysis of RNA isolated from acinar cells of lacrimal glands revealed that they expressed CRISP-1 and CRISP-2 [2].

Biological context of Crisp2

• Testosterone treatment of C3H/HeJ female mice was followed by an upregulation of the steady-state CRISP-1 but not CRISP-2 transcript levels [2].
• CRISP2, originally known as Tpx-1, is a cysteine-rich secretory protein specifically expressed in male haploid germ cells [3].
• A testis-specific gene Tpx-1, located between Pgk-2 and Mep-1 on mouse chromosome 17, was isolated from a cosmid clone, and its cDNA sequences were determined [4].
• Tpx-1 is a testis-specific gene that maps on mouse Chromosome (Chr) 17 [5].
• This result suggests that the ancestor of Tpx-1 acquired exons 9 and 10 after its divergence from the ancestors of the plant and insect proteins [5].

Anatomical context of Crisp2

• Autoantigen 1 of the guinea pig sperm acrosome is the homologue of mouse Tpx-1 and human TPX1 and is a member of the cysteine-rich secretory protein (CRISP) family [6].
• CRISP-1 and CRISP-2 transcripts were detected as early as 22 days after birth in the epididymis and testis, respectively, whereas CRISP-3 mRNA was visible only from day 30 in the salivary gland [7].
• Another transcript, TET7, was the human homologue of rat Tpx-1, which functions in the specific interaction of spermatogenic cells with Sertoli cells [8].

Other interactions of Crisp2

• A testis-specific gene Tpx-1 maps between Pgk-2 and Mep-1 on mouse chromosome 17 [9].

Analytical, diagnostic and therapeutic context of Crisp2

• In situ hybridization of testicular sections showed that Tpx-1 is transcribed abundantly by haploid male germ cells [5].

References