Formin Binding Protein 3 (FNBP3)

The deduced protein is homologous to mouse Fbp11, a formin (FMN1)-binding WW domain protein involved in spliceosome function. Database analysis revealed 2 additional HYPA splice variants. Northern blot analysis detected a major HYPA variant of about 4.2 kb in all adult and fetal tissues examined. Additional transcripts of 3.4 to 3.7 kb, 7.2 kb, and 7.9 kb showed tissue-specific expression.

Highest HYPA expression was detected in adult testis and in fetal kidney, liver, and lung.Variant-1 encodes a deduced 957-amino acid protein, and variant-2 encodes a deduced 915-amino acid protein that lacks a 42-amino acid sequence near the N terminus. Both proteins contain 2 WW domains, 2 FF domains, and a bipartite nuclear localization signal.