Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Hop is a tetratricopeptide repeat domain (TPR)-containing co-chaperone that is able to directly associate with both Hsp70 and Hsp90. Previous data showed that the TPR2A-domain is the primary site for dimerization and that the TPR2B-domain may also play a role in dimerization. We present Hop-D456G, a mutant within the TPR2B-domain, that is a mixture of monomeric and dimeric species.174492498Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fogarty International Center [NIH-R03TW007437]Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fogarty International Center [NIH-R03TW007437]