Characterization of hnRNP A2 and B1 using monoclonal antibodies: intracellular distribution and metabolism through cell cycle

Heterogeneous nuclear ribonucleoprotein (hnRNP) A2/B1 are nuclear RNA bindi ng proteins involved in pre-RNA processing. The alternative splicing of the second mini exon of A2/B1 gene produces A2 and less abundant B1. It has be en reported that patients with autoimmune diseases frequently have blood au toantibody valence for A2/B1, and recently that the overexpression. especia lly of B1, is useful for detecting cancels in early stage. Three anti-A2/B1 monoclonal antibodies were developed using recombinant A2 protein and synt hesized peptides around the second splicing sits. Three antibodies could se parately recognize A2 and B1. and their specificity made them useful in the study of the biochemical and functional properties of A2 and B1. These ant ibodies have demonstrated differences between A2 and B1 in the intracellula r distribution and in the metabolism through cell cycle. They are valuable reagents to clarify the clinical significance of A2/B1 in autoimmune diseas es and cancers. (C) 2001 Elsevier Science B.V. All rights reserved.