twinfilin-1; protein A6; protein tyrosine kinase 9 (TWF1, PTK9)

Function

• sequesters G-actin
• prevents actin filament assembly
• caps barbed ends of filaments
• regulates cell motility
• role in clathrin-mediated endocytosis & distribution of endocytic organelles (putative)
• phosphorylated on Ser & Thr
• interacts with capping protein
• interacts with TWF2 & PI(4,5)P2 (putative)
  • when bound to PI(4,5)P2, it is down-regulated (putative)

Structure

• belongs to the actin-binding proteins ADF family Twinfilin subfamily
• contains 2 ADF-H domains

Compartment

• cytoplasm, cytoskeleton
• diffuse cytoplasmic localization
• perinuclear & G-actin-rich cortical actin structures sublocalization
• also found at membrane ruffles & cell-cell contacts (putative)

Alternative splicing

named isoforms=3

Expression

• expressed in colon, testis, ovary, prostate & lung > brain, bladder & heart
• not detected in liver

Notes

• originally thought to have protein tyrosine kinase activity

More general terms

• phosphoprotein

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=5756
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:5756
• OMIM: https://mirror.omim.org/entry/610932
• UniProt: http://www.uniprot.org/uniprot/Q12792.html