Tau isoforms which contain the domain encoded by exon 6 and their role in neurite elongation

Neurobiology of Developmental Disorders, Shriver Center for Mental Retardation, Waltham, Massachusetts 02452, USA.
Journal of Cellular Biochemistry (Impact Factor: 3.37). 04/2004; 91(5):880-95. DOI: 10.1002/jcb.20029
Source: PubMed

ABSTRACT The regulation of tau protein expression during different stages of cellular differentiation and development as well as its functional role in morphogenesis, neurofibrillary tangle formation, and neurodegeneration have been topics of extensive study but have not been completely clarified yet. Tau undergoes complex regulated splicing in the mammalian nervous system. Our previous study with tau exon 6 demonstrated that it shows a splicing regulation profile which is distinct from that of the other tau exons as well as a unique expression pattern which is spatially and temporally regulated. In this study, we investigated the expression, localization, and effects of tau isoforms which contain exon 6 in neuroblastoma cells which stably overexpress them. We found that expression of one particular combination of tau exons (the longest adult isoform plus the domain of exon 6) significantly inhibits neurite elongation.

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