Identification and expression analysis of novel Jakmip1 transcripts.

Janus kinase and microtubule interacting protein 1, (Jakmip1) conserved in vertebrates and predominantly expressed in neural tissues, was identified for its ability to bind Tyk2, a member of the Janus kinase (Jak) family of non-receptor tyrosine kinases. Recently Jakmip1 was also identified as an interacting partner of GABA(B)R1 and as a regulatory protein of GABA(B)R2 mRNA. We have confirmed that this gene is highly expressed in brain and retina tissues and it is also present at lower levels in other tissues. We have identified four new transcripts of 2975 bp, 1743 bp, 2189 bp and 2420 bp respectively, named Jakmip1B, Jakmip1C, Jakmip1D and Jakmip1E. The involvement of the Janus kinase pathway in the development of mouse retina and in the control of survival and proliferation of human retinal ganglion cells, together with the restricted Jakmip1 gene expression pattern, may suggest this gene is a putative candidate for neuro-degenerative and retinal diseases. For this reason, a mutation analysis of the Jakmip1 gene in a panel of 50 unrelated patients with retinitis pigmentosa has been performed, revealing no pathogenic mutations.