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Interaction of the endocytic scaffold protein Pan1 with the type I myosins contributes to the late stages of endocytosis.

ABSTRACT: The yeast endocytic scaffold Pan1 contains an uncharacterized proline-rich domain (PRD) at its carboxy (C)-terminus. We report that the pan1-20 temperature-sensitive allele has a disrupted PRD due to a frame-shift mutation in the open reading frame of the domain. To reveal redundantly masked functions of the PRD, synthetic genetic array screens with a pan1DeltaPRD strain found genetic interactions with alleles of ACT1, LAS17 and a deletion of SLA1. Through a yeast two-hybrid screen, the Src homology 3 domains of the type I myosins, Myo3 and Myo5, were identified as binding partners for the C-terminus of Pan1. In vitro and in vivo assays validated this interaction. The relative timing of recruitment of Pan1-green fluorescent protein (GFP) and Myo3/5-red fluorescent protein (RFP) at nascent endocytic sites was revealed by two-color real-time fluorescence microscopy; the type I myosins join Pan1 at cortical patches at a late stage of internalization, preceding the inward movement of Pan1 and its disassembly. In cells lacking the Pan1 PRD, we observed an increased lifetime of Myo5-GFP at the cortex. Finally, Pan1 PRD enhanced the actin polymerization activity of Myo5-Vrp1 complexes in vitro. We propose that Pan1 and the type I myosins interactions promote an actin activity important at a late stage in endocytic internalization.

SUBMITTER: Barker SL

PROVIDER: S-EPMC1949359 | biostudies-other | 2007 Aug

REPOSITORIES: biostudies-other

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Interaction of the endocytic scaffold protein Pan1 with the type I myosins contributes to the late stages of endocytosis.

Barker Sarah L SL Lee Linda L Pierce B Daniel BD Maldonado-Báez Lymarie L Drubin David G DG Wendland Beverly B

Molecular biology of the cell 20070523 8

The yeast endocytic scaffold Pan1 contains an uncharacterized proline-rich domain (PRD) at its carboxy (C)-terminus. We report that the pan1-20 temperature-sensitive allele has a disrupted PRD due to a frame-shift mutation in the open reading frame of the domain. To reveal redundantly masked functions of the PRD, synthetic genetic array screens with a pan1DeltaPRD strain found genetic interactions with alleles of ACT1, LAS17 and a deletion of SLA1. Through a yeast two-hybrid screen, the Src homo ...[more]

PMID: 17522383

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Dataset Information

Interaction of the endocytic scaffold protein Pan1 with the type I myosins contributes to the late stages of endocytosis.

Publications

Interaction of the endocytic scaffold protein Pan1 with the type I myosins contributes to the late stages of endocytosis.

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