Assembly of splicing complexes on exon 11 of the human insulin receptor gene does not correlate with splicing efficiency in-vitro

Background  

Incorporation of exon 11 of the insulin receptor gene is both developmentally and hormonally-regulated. Previously, we have shown the presence of enhancer and silencer elements that modulate the incorporation of the small 36-nucleotide exon. In this study, we investigated the role of inherent splice site strength in the alternative splicing decision and whether recognition of the splice sites is the major determinant of exon incorporation.     

Variable number tandem repeat polymorphism of the mucin genes located in the complex on 11p15.5

A family of four genes that encode major secreted mucins (MUC6, MUC2, MUC5AC and MUC5B) map to within 400kb on chromosome 11p15.5. These genes contain long stretches of tandem repeats of sequence that encode serine- and threonine-rich domains but that otherwise show no similarity from gene to gene, and regions of unique sequence domains that do show evidence of sequence homology. We have previously reported the existence of polymorphism in three of these genes but the extent and nature of this allelic variation is now described here in detail. Variable number tandem repeat polymorphisms of MUC6, MUC2 and MUC5AC are predicted to encode mucin polypeptides that differ in length. In the case of MUC2 and MUC6 these length differences are substantial (up to twofold). MUC5B in contrast does not show common allele length variation. Three MUC2 mutations are reported, none of which are associated with the meiotic recombinations previously observed in this region of chromosome 11. Received: 24 July 1997 / Accepted: 13 November 1997     

Evidence from pulse radiolysis and flash photolysis of the environment of tryptophan and tyrosine in the coat protein of fd phage

Charge transfer has been observed between oxidised tryptophan-26 units and the tyrosine-21 or -24 of the coat protein of fd phage. The transfer is likely to be intramolecular. The rates suggest that the aromatic units are in a rigid region and that they may have at least two different environments. No apparent interaction occurs with the DNA, consistent with tryptophan and tyrosine units not being in contact with the bases.