Identification of alternative splicing form of Stat2.

We identified alternatively spliced forms of Stat2 in human and mouse mRNAs. The spliced forms are generated by reading through the intron between exon 20 and 21, which correspond to the region encoding SH2 domain. The spliced forms contain a stop codon in SH2 domain, and therefore give rise to a short form of Stat2 when the mRNAs are translated. The putative translated proteins lack half of the SH2 domain, the tyrosine phosphorylation site required for dimerization (or oligomerization) and DNA binding, and C-terminal activation domain. The significance of these spliced forms is discussed.