A mutation in Rab27a causes the vesicle transport defects observed in ashen mice

Scott M. Wilson, Richard Yip, Deborah A. Swing, T. Norene O'Sullivan, Yuke Zhang, Edward K. Novak, Richard T. Swank, Liane B. Russell, Neal G. Copeland, Nancy A. Jenkins

Research output: Contribution to journalArticlepeer-review

339 Scopus citations


The dilute (d), leaden (In), and ashen (ash) mutations provide a unique model system for studying vesicle transport in mammals. All three mutations produce a lightened coat color because of defects in pigment granule transport. In addition, all three mutations are suppressed by the semidominant dilute-suppressor (dsu), providing genetic evidence that these mutations function in the same or overlapping transport pathways. Previous studies showed that d encodes a major vesicle transport motor, myosin-VA, which is mutated in Griscelli syndrome patients. Here, using positional cloning and bacterial artificial chromosome rescue, we show that ash encodes Rab27a. Rab GTPases represent the largest branch of the p21 Ras superfamily and are recognized as key players in vesicular transport and organelle dynamics in eukaryotic cells. We also show that ash mice have platelet defects resulting in increased bleeding times and a reduction in the number of platelet dense granules. These defects have not been reported for d and ln mice. Collectively, our studies identify Rab27a as a critical gene for organelle-specific protein trafficking in melanocytes and platelets and suggest that Rab27a functions in both MyoVa dependent and independent pathways.

Original languageEnglish (US)
Pages (from-to)7933-7938
Number of pages6
JournalProceedings of the National Academy of Sciences of the United States of America
Issue number14
StatePublished - Jul 5 2000

ASJC Scopus subject areas

  • General


Dive into the research topics of 'A mutation in Rab27a causes the vesicle transport defects observed in ashen mice'. Together they form a unique fingerprint.

Cite this