NIMA-related kinases: isolation and characterization of murine nek3 and nek4 cDNAs, and chromosomal localization of nek1, nek2 and nek3

The Aspergillus NIMA kinase plays a key role in controlling entrance into m itosis, and recent evidence suggests that mammalian NIMA-related kinases pe rform similar functions. We report here the cloning of the mouse nek3 and n ek4 genes. Mouse nek3 is probably the ortholog of the partially sequenced, human nek3, whereas murine nek4 cDNA is probably the ortholog of human STK2 . Nek4 is highly conserved between mouse and human, whereas Nek3 is somewha t less conserved (96.5 and 88% identity in the kinase domains, respectively ). Northern analysis shows preferential expression of nek3; in mitotically active tissue, whereas nek4 is highly abundant in the testis. Within the de veloping testicular germ cells, in-situ analysis demonstrated that nek1, 2 and 4 exhibit differential patterns of expression, suggesting overlapping, but non-identical functions. Linkage analysis, using the mouse recombinant inbred strain panel (BXD), was used to localize nek1, 2 and 3. nek1 was map ped between Cpe and D8Mit8 on chromosome 8 at around 32 cM, nek2 was mapped to the distal region of chromosome I, and nek3 was mapped to the most cent romeric region of chromosome 8. (C) 1999 Elsevier Science B.V. All rights : reserved.