High impact information on SEC66

• We demonstrate that Sec62p, Sec71p and Sec72p form a translocon subcomplex that engages secretory precursors at the membrane site of the ER translocation machinery [1].
• Similar COP1-binding motifs containing an essential aromatic residue were identified in the cytoplasmic domain of an ER-resident protein, Sec71p, and in an ER retention motif previously characterized in the CD3epsilon chain of the T-cell receptor [2].
• Taken together, these results suggest a direct role for Sec63p, Sec71p, and Sec72p in nuclear membrane fusion and argue against the alternative interpretation that the karyogamy defects result as an indirect consequence of the impaired membrane translocation of another component(s) required for the process [3].
• Disruption of the genes encoding other Sec63p-associated proteins (Sec71p and Sec72p) also results in karyogamy defects [3].
• We demonstrate here that the transmembrane domain (TMD) of Sec71p, a type-III membrane protein, contains an ER localization signal, which is required for physical recognition by Rer1p [4].

Biological context of SEC66

• KAR7 is allelic to SEC71, a gene involved in protein translocation into the endoplasmic reticulum [5].
• DNA sequence analysis of SEC66 predicts a 23-kDa protein with no obvious NH2-terminal signal sequence but with one domain of sufficient length and hydrophobicity to span a lipid bilayer [6].

Associations of SEC66 with chemical compounds

• HSS1 is identical to SEC66, which encodes a glycoprotein complexed with SEC62p and SEC63p [7].

Other interactions of SEC66

• Moreover, in sec71 mutants, Kar5p was absent from the SPB and was not detected by Western blot or immunoprecipitation of pulse-labeled protein [5].
• The mutants were contained in three complementation groups, which we have named SEC70, SEC71, and SEC72 [8].
• Intracellular fluorescence images for Mid1 were the same as those for the ER marker protein Sec71 but quite different from those of the Golgi protein Ypt1 [9].
• In the work on yeast Saccharomyces cerevisiae, we have demonstrated that transmembrane domains of a subset of ER membrane proteins including Sec12p, Sec71p and Sec63p contain novel ER retrieval signals [10].

References