Saitohin, Which Is Nested Within the Tau Gene, Interacts With Tau and Abl and its Human-Specific Allele Influences Abl Phosphorylation

Department of Cell Biology, University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA.
Journal of Cellular Biochemistry (Impact Factor: 3.26). 11/2011; 112(11):3482-8. DOI: 10.1002/jcb.23279
Source: PubMed


Saitohin (STH) is a gene unique to humans and their closest relatives whose function is not yet known. STH contains a single polymorphism (Q7R); the Q allele is human-specific and confers susceptibility to several neurodegenerative diseases. In previous work, we discovered that STH interacts with Peroxiredoxin 6 (Prdx6), a unique member of that family which is bifunctional and whose levels increase in Pick's disease. In this study, we report that STH also interacts with tau and the non-receptor tyrosine kinase c-Abl (Abl). Furthermore, Abl phosphorylates STH on its single tyrosine residue and STH increases tyrosine phosphorylation by Abl. The effect of Saitohin on Abl-mediated phosphorylation appears to be allele-specific, providing evidence for a new cellular function for STH.

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Available from: Athena Andreadis, Jul 24, 2014
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    • "The A allele is remarkably common in humans; however, all nonhuman primates are homozygous for the G allele, which makes the A allele a human-specific marker (Conrad et al. 2004; Holzer et al. 2004). Thus, the G allele is the ancestral allele, and the A allele evolved after the hominine lineages separated from the other primates (Wang et al. 2011). The STH A allele is overrepresented in several neurodegenerative diseases such as progressive supranuclear palsy, frontotemporal dementia, Alzheimer's disease, and Parkinson's disease (Conrad et al. 2002; Wider et al. 2010; Levecque et al. 2004; Andreadis 2012). "
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    • "In this regions is present various PPXXP or PXXP motifs which allow Tau protein to interacts with SH3 domains of diverse proteins such as Src family members like Fyn, Lck, Src (Lee, 2005; Lee et al., 1998; Scales et al., 2011) and others like PCL-γ (Hwang et al., 1996; Jenkins &Johnson, 1998). Is also mentioned that STH interacts with Tau and Abl and influences in Abl phosphorylation (Wang et al., 2011), but this phenomena needs further research. "
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