This domain (also known as the Brl domain) is required for assembly of functional endoplasmic reticulum translocons [2].

1: Proteins of the endoplasmic-reticulum-associated degradation pathway: domain detection and function prediction. Ponting CP; Biochem J 2000;351:527-535. PMID:11023840

2: The Brl domain in Sec63p is required for assembly of functional endoplasmic reticulum translocons. Jermy AJ, Willer M, Davis E, Wilkinson BM, Stirling CJ; J Biol Chem. 2006;281:7899-7906. PMID:16368690