New paper from Alberto Kornblihtt's group
Congratulations to Alberto Kornblihtt's group.
Their new paper has been recently published on-line in PNAS:
Schor, I. E., Rascovan, N., Pelisch, F., Alló, M. & Kornblihtt, A. R. Neuronal cell depolarization induces intragenic chromatin modifications affecting NCAM alternative splicing. Proc. Natl. Acad. Sci. USA (2009), in press.
Indeed changes in the elongation speed of transcription modulate alternative splicing choices, affecting the timing at which the nascent mRNA precursors expose sites important for elimination of introns. A way of modultaion elongation, different from RNA polymerase II hyperphosphorylation caused by UV, is by modulating the compaction of chromatin: the more compact the chromatin the more difficult to transcribe it. The PNAS paper shows how this mechanism operates on a gene that is relevant for the differentiation of neuronal cells. We found that neuronal activity induces changes in the splicing pattern of the neural cell adhesion molecule (NCAM) in part by increasing histone acetylation and chromatin relaxation, leading to a state that would facilitate transcription elongation and, hence, affect NCAM alternative splicing.
You can find a full version of the paper here.