C. elegans Dynamin mediates the signaling of phagocytic receptor CED-1 for the engulfment and degradation of apoptotic cells.
Dynamins are large GTPases that act in multiple vesicular trafficking events. We identified 14 loss-of-function alleles of the C. elegans dynamin gene, dyn-1, that are defective in the removal of apoptotic cells. dyn-1 functions in engulfing cells to control the internalization and degradation of apoptotic cells. dyn-1 acts in the genetic pathway composed of ced-7 (ABC transporter), ced-1 (phagocytic receptor), and ced-6 (CED-1's adaptor). DYN-1 transiently accumulates to the surface of pseudopods in a manner dependent on ced-1, ced-6, and ced-7, but not on ced-5, ced-10, or ced-12. Abnormal vesicle structures accumulate in engulfing cells upon dyn-1 inactivation. dyn-1 and ced-1 mutations block the recruitment of intracellular vesicles to pseudopods and phagosomes. We propose that DYN-1 mediates the signaling of the CED-1 pathway by organizing an intracellular vesicle pool and promoting vesicle delivery to phagocytic cups and phagosomes to support pseudopod extension and apoptotic cell degradation.
Yu
Xiaomeng
X
Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030, USA.
Odera
Sampeter
S
Chuang
Chin-Hua
CH
Lu
Nan
N
Zhou
Zheng
Z
D000483:Alleles; D000595:Amino Acid Sequence; D000818:Animals; D017209:Apoptosis; D017173:Caenorhabditis elegans / Q000166:cytology / Q000196:embryology / Q000378:metabolism / Q000502:physiology / Q000648:ultrastructure; D029742:Caenorhabditis elegans Proteins / Q000378:metabolism*; D017124:Conserved Sequence; D034281:Dynamins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism* / Q000502:physiology / Q000648:ultrastructure; D004625:Embryo, Nonmammalian / Q000648:ultrastructure; D015801:Helminth Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism* / Q000502:physiology / Q000648:ultrastructure; D008565:Membrane Proteins / Q000378:metabolism*; D008954:Models, Biological; D008969:Molecular Sequence Data; D009154:Mutation; D010587:Phagocytosis; D017434:Protein Structure, Tertiary; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction
D029742:Caenorhabditis elegans Proteins; D015801:Helminth Proteins; D008565:Membrane Proteins; C422043:ced-1 protein, C elegans; C511792:Dyn-1 protein, C elegans; D034281:Dynamins