testis-specific serine/threonine protein kinase 2; TSK-2; TSK2; TSSK-2; testis-specific kinase 2; DiGeorge syndrome protein G; DGS-G;; serine/threonine protein kinase 22B (TSSK2, DGSG, SPOGA2, STK22B)

Function

• testis-specific serine/threonine protein kinase
• required during spermatid development
• phosphorylates TSKS at Ser-288 & SPAG16
• role in late stages of spermatogenesis, during the reconstruction of the cytoplasm
• during spermatogenesis, required for transformation of a ring-shaped structure around the base of the flagellum originating from the chromatoid body
• activated by phosphorylation on Thr-174, & potentially by autophosphorylation (putative)
• autophosphorylated
• interacts with TSSK1B

Kinetic parameters:

• KM=10 uM for ATP

Cofactor: Mg+2

Structure

• belongs to the protein kinase superfamily, CAMK Ser/Thr protein kinase family
• contains 1 protein kinase domain

Compartment

• cytoplasm, cytoskeleton, centrosome, centriole
• present in cytoplasm of elongating spermatids
• in spermatozoa, localizes in the equatorial segment, neck, the midpiece & in a specific sperm head compatment (putative)
• in spermatids, concentrates in centrioles during flagellogenesis

Expression

• testis-specific
• present in mature spermatozoa (at protein level)

Notes

• TSSK1B might be used as a target for male contraception &/or intra-vaginal spermicides

More general terms

• serine/threonine protein kinase 22

Additional terms

• DiGeorge syndrome; velocardiofacial syndrome; pharyngeal pouch syndrome

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=23617
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:23617
• OMIM: https://mirror.omim.org/entry/610710
• UniProt: http://www.uniprot.org/uniprot/Q96PF2.html