Human-Mouse Kinome Update

Differences between human and mouse kinomes

95% of all human protein kinases have mouse orthologs. The differences in kinase count between the two genomes are mostly in recently-evolved and poorly-annotated genes, suggesting that most do not have particularly important functions.

Retrotransposed gene copies

Three human-specific genes are intronless (retrotrasponsed) close copies of intron-containing kinases. These are TAF1L (duplicate of TAF1, expressed specifically in testis), CK1a2 (CK1a1 copy) , and PKACg (PKACa copy), all appears to be expressed, functional genes, under evolutionary constraint.

Both species have additional retrotransposed copies which are too recent to use Ka/Ks analysis to determine if they are under selective pressure. They have been given the "-rs" (-related sequence) tag. They are STLK6-rs and CK2a2-rs in human, and CK2a2-rs and NDR2-rs in mouse. The CK2a2-rs genes are not orthologous: each is more similar to it's in-species paralog than to the other -rs and they occupy different genomic loci.

Pseudogenized genes

KSGC, CYGX, TSSK5 and PLK5 are functional genes in mouse, and found in human as pseudogenes. Similarly, CDK3 is a human gene with an orthologous mouse pseudogene.

Others

PSKH2, DRAK1 and GPRK7 are found in human and thought to be lost from mouse, due to presence in other mammals.

The large expansion of MARK kinases in mouse has a largely independent similar expansion in rat. Human has 25 MARK pseudogenes, but none are obvious orthologs of the mouse genes.

Human-specific Kinases

PRKY is a likely primate-specific duplication of the X-chromosome PRKX gene, found on the Y chromosome. The human gene is likely a pseudogene (details).

TAF1L is a retrotransposed copy of TAF1 which is expressed in the testis and under evolutionary constraint, as measured by Ka/Ks. It is also found in chimp.

CDK3 is a pseudogene in mouse, though full-length in the related Mus spretus. It is also a pseudogene in rat. It appears to be a mammalian-specific copy of CDK2.

Mouse-specific Kinases

PLK5 is an active gene in mouse, but a pseudogene in human (details).

TSSK5 is also detected as a pseudogene in human. The TSSK family is among the most dynamic in vertebrate evolution, with multiple duplications and deletions seen. This may be related to it's expression in the testis and possible function in reproduction.