id	author	title	date	pages	extension	mime	words	sentences	flesch	summary	cache	txt
cord-015237-8cxfa8wf	nan	Structure Watch	2005		.txt	text/plain	274	23	66	The solution structures of the four RNA-binding domains (RBDs) of polypyrimidine-tract-binding protein-1 (PTB1) in complex with RNA have now been solved by Oberstrass et al., leading to new models for the function of PTB1 as a repressor of alternative splicing. used NMR to look at the structure of RBD1-4 in complex with a 5′-CUCUCU-3′ oligonucleotide, which is a common feature of intronic regulatory sequences. Each RBD binds independently to one RNA molecule and recognizes a different consensus sequence within the oligonucleotide. The nucleotides interact with the flat β-sheet surface of each RBD but, unlike other RBD-RNA structures, the third β-strand is only weakly involved in RNA binding. A single PTB1 molecule can therefore bring two distant pyrimidine tracts into close proximity and induce RNA looping -a feature that has led to the proposal of various models for the function of this protein in alternative splicing. Structure of PTB bound to RNA: specific binding and implications for splicing regulation	./cache/cord-015237-8cxfa8wf.txt	./txt/cord-015237-8cxfa8wf.txt