A Coiled-Coil Domain of Melanophilin Is Essential for Myosin Va Recruitment and Melanosome Transport in Melanocytes
A Coiled-Coil Domain of Melanophilin Is Essential for Myosin Va Recruitment and Melanosome Transport in Melanocytes
Melanophilin (Mlph) regulates retention of melanosomes at the peripheral actin cytoskeleton of melanocytes, a process essential for normal mammalian pigmentation. Mlph is proposed to be a modular protein binding the melanosome-associated protein Rab27a, Myosin Va (MyoVa), actin, and microtubule end-binding protein (EB1), via distinct N-terminal Rab27a-binding domain (R27BD), medial MyoVa-binding domain (MBD), and C-terminal actin-binding domain (ABD), respectively. We developed a novel melanosome transport assay using a Mlph-null cell line to study formation of the active Rab27a:Mlph:MyoVa complex. Recruitment of MyoVa to melanosomes correlated with rescue of melanosome transport and required intact R27BD together with MBD exon F–binding region (EFBD) and unexpectedly a potential coiled-coil forming sequence within ABD. In vitro binding studies indicate that the coiled-coil region enhances binding of MyoVa by Mlph MBD. Other regions of Mlph reported to interact with MyoVa globular tail, actin, or EB1 are not essential for melanosome transport rescue. The strict correlation between melanosomal MyoVa recruitment and rescue of melanosome distribution suggests that stable interaction with Mlph and MyoVa activation are nondissociable events. Our results highlight the importance of the coiled-coil region together with R27BD and EFBD regions of Mlph in the formation of the active melanosomal Rab27a-Mlph-MyoVa complex.
- University of Coimbra Portugal
- Imperial College London United Kingdom
- University of London United Kingdom
- St George's, University of London United Kingdom
Melanosomes, Myosin Heavy Chains, Myosin Type V, Intracellular Membranes, Protein Structure, Secondary, Protein Structure, Tertiary, Mice, Inbred C57BL, Mice, Protein Transport, Animals, Humans, Melanocytes, Amino Acids, Carrier Proteins, Adaptor Proteins, Signal Transducing, Cell Line, Transformed, Protein Binding
Melanosomes, Myosin Heavy Chains, Myosin Type V, Intracellular Membranes, Protein Structure, Secondary, Protein Structure, Tertiary, Mice, Inbred C57BL, Mice, Protein Transport, Animals, Humans, Melanocytes, Amino Acids, Carrier Proteins, Adaptor Proteins, Signal Transducing, Cell Line, Transformed, Protein Binding
10 Research products, page 1 of 1
- 2017IsRelatedTo
- 2017IsRelatedTo
- 2017IsRelatedTo
- 2017IsRelatedTo
- 2017IsRelatedTo
- 2017IsRelatedTo
- 2017IsRelatedTo
- 2017IsRelatedTo
- 2017IsRelatedTo
- 2017IsRelatedTo
citations This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).83 popularity This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network.Top 10% influence This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).Top 10% impulse This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network.Top 10%
