High impact information on HRR25

• Taken together, the hrr25 mutant phenotypes and the features of the gene product indicate that HRR25 is a distinctive member of the protein kinase superfamily [1].
• The NH2-terminus of HRR25 contains the hallmark features of protein kinases, whereas the COOH-terminus is rich in proline and glutamine [1].
• Homozygotes of hrr25-1 were unable to sporulate and disruption and deletion of HRR25 interfered with mitotic and meiotic cell division [1].
• The amino acid sequence identifies the CKI as the alpha-CKI isoform, which is 62% identical to the HRR25 protein kinase [2].
• This localization suggests that alpha-CKI, like HRR25, plays a role in the segregation of chromosomes during mitosis and may be cell cycle-regulated both in humans and in yeast [2].

Biological context of HRR25

• Recently, cDNA clones encoding several bovine CKI isoforms have been sequenced that show high sequence identity to the HRR25 gene product of the budding yeast Saccharomyces cerevisiae; HRR25 is required for normal cellular growth, nuclear segregation, DNA repair, and meiosis [2].
• A budding yeast isoform of CKI, HRR25, has been implicated in DNA repair responses [3].

Other interactions of HRR25

• This is most evident for yeast genes CBK1, HRR25, and SNF1 and the kinase family S6K [4].
• RST2 turned out to be identical to HRR25, a gene encoding a dual-specificity casein kinase I in yeast [5].
• Single-copy complementation identified HRR25, which codes for casein kinase I (CKI), as KTI14 [6].

References