Publication Date:
2013-07-13
Description:
A classic feature of apoptotic cells is the cell-surface exposure of phosphatidylserine (PtdSer) as an "eat me" signal for engulfment. We show that the Xk-family protein Xkr8 mediates PtdSer exposure in response to apoptotic stimuli. Mouse Xkr8(-/-) cells or human cancer cells in which Xkr8 expression was repressed by hypermethylation failed to expose PtdSer during apoptosis and were inefficiently engulfed by phagocytes. Xkr8 was activated directly by caspases and required a caspase-3 cleavage site for its function. CED-8, the only Caenorhabditis elegans Xk-family homolog, also promoted apoptotic PtdSer exposure and cell-corpse engulfment. Thus, Xk-family proteins have evolutionarily conserved roles in promoting the phagocytosis of dying cells by altering the phospholipid distribution in the plasma membrane.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Suzuki, Jun -- Denning, Daniel P -- Imanishi, Eiichi -- Horvitz, H Robert -- Nagata, Shigekazu -- Howard Hughes Medical Institute/ -- New York, N.Y. -- Science. 2013 Jul 26;341(6144):403-6. doi: 10.1126/science.1236758. Epub 2013 Jul 11.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Medical Chemistry, Graduate School of Medicine, Kyoto University, Yoshida-Konoe, Sakyo-ku, Kyoto, Kyoto 606-8501, Japan.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23845944" target="_blank"〉PubMed〈/a〉
Keywords:
Amino Acid Sequence
;
Animals
;
*Apoptosis
;
Apoptosis Regulatory Proteins/chemistry/genetics/*metabolism
;
Caenorhabditis elegans Proteins/*metabolism
;
Calcium/metabolism
;
Caspases/metabolism
;
Cell Line
;
Cell Line, Tumor
;
Cell Membrane/*metabolism
;
CpG Islands
;
Humans
;
Macrophages/physiology
;
Membrane Proteins/chemistry/genetics/*metabolism
;
Mice
;
Mice, Knockout
;
Molecular Sequence Data
;
*Phagocytosis
;
Phosphatidylserines/*metabolism
;
Recombinant Fusion Proteins/metabolism
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
