Rab14 is involved in membrane trafficking between the Golgi complex and endosomes.
Rab GTPases are localized to various intracellular compartments and are known to play important regulatory roles in membrane trafficking. Here, we report the subcellular distribution and function of Rab14. By immunofluorescence and immunoelectron microscopy, both endogenous as well as overexpressed Rab14 were localized to biosynthetic (rough endoplasmic reticulum, Golgi, and trans-Golgi network) and endosomal compartments (early endosomal vacuoles and associated vesicles). Notably overexpression of Rab14Q70L shifted the distribution toward the early endosome associated vesicles, whereas the S25N and N124I mutants induced a shift toward the Golgi region. A similar, although less pronounced, redistribution of the transferrin receptor was also observed in cells overexpressing Rab14 mutants. Impairment of Rab14 function did not however affect transferrin uptake or recycling kinetics. Together, these findings suggest that Rab14 is involved in the biosynthetic/recycling pathway between the Golgi and endosomal compartments.
Genentech Inc., South San Francisco, California 94080, USA.
Jagath R
JR
Junutula
Ann M
AM
De Maziére
Andrew A
AA
Peden
Karen E
KE
Ervin
Raj J
RJ
Advani
Suzanne M
SM
van Dijk
Judith
J
Klumperman
Richard H
RH
Scheller
D000818:Animals; D000906:Antibodies / Q000276:immunology; D002460:Cell Line; D002462:Cell Membrane / Q000502:physiology; D011992:Endosomes / Q000502:physiology* / Q000648:ultrastructure; D015870:Gene Expression; D006056:Golgi Apparatus / Q000502:physiology* / Q000648:ultrastructure; D049452:Green Fluorescent Proteins / Q000032:analysis; D006801:Humans; D042541:Intracellular Space / Q000648:ultrastructure; D051379:Mice; D008856:Microscopy, Fluorescence; D017354:Point Mutation / Q000235:genetics; D021381:Protein Transport / Q000502:physiology; D051381:Rats; D011990:Receptors, Transferrin / Q000032:analysis / Q000378:metabolism; D014168:Transferrin / Q000378:metabolism; D020691:rab GTP-Binding Proteins / Q000032:analysis / Q000235:genetics / Q000502:physiology*
D000906:Antibodies; D011990:Receptors, Transferrin; D014168:Transferrin; C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins; C494592:Rab14 protein, rat; D020691:rab GTP-Binding Proteins