Golgi-to-endoplasmic reticulum (ER) retrograde traffic in yeast requires Dsl1p, a component of the ER target site that interacts with a COPI coat subunit.

Content Provider	Semantic Scholar
Author	Vanrheenen, S. M.
Copyright Year	2001
Abstract	DSL1 was identified through its genetic interaction with SLY1, which encodes a t-SNARE-interacting protein that functions in endoplasmic reticulum (ER)-to-Golgi traffic. Conditional dsl1 mutants exhibit a block in ER-to-Golgi traffic at the restrictive temperature. Here, we show that dsl1 mutants are defective for retrograde Golgi-to-ER traffic, even under conditions where no anterograde transport block is evident. These results suggest that the primary function of Dsl1p may be in retrograde traffic, and that retrograde defects can lead to secondary defects in anterograde traffic. Dsl1p is an ER-localized peripheral membrane protein that can be extracted from the membrane in a multiprotein complex. Immunoisolation of the complex yielded Dsl1p and proteins of approximately 80 and approximately 55 kDa. The approximately 80-kDa protein has been identified as Tip20p, a protein that others have shown to exist in a tight complex with Sec20p, which is approximately 50 kDa. Both Sec20p and Tip20p function in retrograde Golgi-to-ER traffic, are ER-localized, and bind to the ER t-SNARE Ufe1p. These findings suggest that an ER-localized complex of Dsl1p, Sec20p, and Tip20p functions in retrograde traffic, perhaps upstream of a Sly1p/Ufe1p complex. Last, we show that Dsl1p interacts with the delta-subunit of the retrograde COPI coat, Ret2p, and discuss possible roles for this interaction.
File Format	PDF HTM / HTML
Alternate Webpage(s)	http://www.molbiolcell.org/content/12/12/3783.full.pdf
PubMed reference number	11739780v1
Volume Number	12
Issue Number	12
Journal	Molecular biology of the cell
Language	English
Access Restriction	Open
Subject Keyword	COPA gene Coat Protein Complex I Eighty Endoplasmic Reticulum Golgi Apparatus Membrane Proteins Staphylococcal Protein A Tissue membrane adenotonsillectomy extrinsic component of membrane mutant
Content Type	Text
Resource Type	Article