Rab GTPase-Myo5B complexes control membrane recycling and epithelial polarization

TY - JOUR

T1 - Rab GTPase-Myo5B complexes control membrane recycling and epithelial polarization

AU - Roland, Joseph T

AU - Bryant, David M

AU - Datta, Anirban

AU - Itzen, Aymelt

AU - Mostov, Keith E

AU - Goldenring, James R

PY - 2011/2/15

Y1 - 2011/2/15

N2 - The Rab GTPases are the largest family of proteins regulating membrane traffic. Rab proteins form a nidus for the assembly of multiprotein complexes on distinct vesicle membranes to regulate particular membrane trafficking pathways. Recent investigations have demonstrated that Myosin Vb (Myo5B) is an effector for Rab8a, Rab10, and Rab11a, all of which are implicated in regulating different pathways for recycling of proteins to the plasma membrane. It remains unclear how specific interactions of Myo5B with individual Rab proteins can lead to specificity in the regulation of alternate trafficking pathways. We examined the relative contributions of Rab/Myo5B interactions with specific pathways using Myo5B mutants lacking binding to either Rab11a or Rab8a. Myo5B Q1300L and Y1307C mutations abolished Rab8a association, whereas Myo5B Y1714E and Q1748R mutations uncoupled association with Rab11a. Expression of Myo5B tails containing these mutants demonstrated that Rab11a, but not Rab8a, was required for recycling of transferrin in nonpolarized cells. In contrast, in polarized epithelial cyst cultures, Myo5B was required for apical membrane trafficking and de novo lumen formation, dependent on association with both Rab8a and Rab11a. These data demonstrate that different combinations of Rab GTPase association with Myo5B control distinct membrane trafficking pathways.

AB - The Rab GTPases are the largest family of proteins regulating membrane traffic. Rab proteins form a nidus for the assembly of multiprotein complexes on distinct vesicle membranes to regulate particular membrane trafficking pathways. Recent investigations have demonstrated that Myosin Vb (Myo5B) is an effector for Rab8a, Rab10, and Rab11a, all of which are implicated in regulating different pathways for recycling of proteins to the plasma membrane. It remains unclear how specific interactions of Myo5B with individual Rab proteins can lead to specificity in the regulation of alternate trafficking pathways. We examined the relative contributions of Rab/Myo5B interactions with specific pathways using Myo5B mutants lacking binding to either Rab11a or Rab8a. Myo5B Q1300L and Y1307C mutations abolished Rab8a association, whereas Myo5B Y1714E and Q1748R mutations uncoupled association with Rab11a. Expression of Myo5B tails containing these mutants demonstrated that Rab11a, but not Rab8a, was required for recycling of transferrin in nonpolarized cells. In contrast, in polarized epithelial cyst cultures, Myo5B was required for apical membrane trafficking and de novo lumen formation, dependent on association with both Rab8a and Rab11a. These data demonstrate that different combinations of Rab GTPase association with Myo5B control distinct membrane trafficking pathways.

KW - Animals

KW - Cell Line

KW - Cell Polarity

KW - DNA Primers

KW - Dogs

KW - Epithelial Cells

KW - Fluorescence Resonance Energy Transfer

KW - Humans

KW - Immunohistochemistry

KW - Membranes

KW - Mice

KW - Multiprotein Complexes

KW - Mutagenesis

KW - Myosin Heavy Chains

KW - Myosin Type V

KW - Protein Transport

KW - RNA Interference

KW - Transferrin

KW - Transport Vesicles

KW - Two-Hybrid System Techniques

KW - rab GTP-Binding Proteins

KW - Journal Article

KW - Research Support, N.I.H., Extramural

KW - Research Support, Non-U.S. Gov't

U2 - 10.1073/pnas.1010754108

DO - 10.1073/pnas.1010754108

M3 - SCORING: Journal article

C2 - 21282656

VL - 108

SP - 2789

EP - 2794

JO - P NATL ACAD SCI USA

JF - P NATL ACAD SCI USA

SN - 0027-8424

IS - 7

ER -