Identification of an interaction between SOX9 and HSP70

The campomelic dysplasia/autosomal sex reversal protein SOX9 is an importan t developmental transcription factor, required for correct bone and testis formation, Through in vitro and in vivo studies we have identified the heat shock protein HSP70 as an interacting partner for SOX9 in chondrocyte and testicular cell lines. HSP70 forms a ternary complex with DNA-bound SOX9, T he interaction between HSP70 and SOX9 is ATP-independent and involves a hig hly conserved region of SOX9 hitherto of unknown function and the C-termina l region of HSP70, Our results implicate HSP70-SOX9 interactions in the ass embly of multi-protein complexes during SOX9-mediated transcription. (C) 20 01 Federation of European Biochemical Societies. Published by Elsevier Scie nce B.V. All rights reserved.