| RRC ID |
54379
|
| 著者 |
Fujimoto T, Nakamura O, Saito M, Tsuru A, Matsumoto M, Kohno K, Inaba K, Kadokura H.
|
| タイトル |
Identification of the physiological substrates of PDIp, a pancreas-specific protein-disulfide isomerase family member.
|
| ジャーナル |
J Biol Chem
|
| Abstract |
About 20 members of the protein-disulfide isomerase (PDI) family are present in the endoplasmic reticulum of mammalian cells. They are thought to catalyze thiol-disulfide exchange reactions within secretory or membrane proteins to assist in their folding or to regulate their functions. PDIp is a PDI family member highly expressed in the pancreas and known to bind estrogen in vivo and in vitro However, the physiological functions of PDIp remained unclear. In this study, we set out to identify its physiological substrates. By combining acid quenching and thiol alkylation, we stabilized and purified the complexes formed between endogenous PDIp and its target proteins from the mouse pancreas. MS analysis of these complexes helped identify the disulfide-linked PDIp targets in vivo, revealing that PDIp interacts directly with a number of pancreatic digestive enzymes. Interestingly, when pancreatic elastase, one of the identified proteins, was expressed alone in cultured cells, its proenzyme formed disulfide-linked aggregates within cells. However, when pancreatic elastase was co-expressed with PDIp, the latter prevented the formation of these aggregates and enhanced the production and secretion of proelastase in a form that could be converted to an active enzyme upon trypsin treatment. These findings indicate that the main targets of PDIp are digestive enzymes and that PDIp plays an important role in the biosynthesis of a digestive enzyme by assisting with the proper folding of the proenzyme within cells.
|
| 巻・号 |
293(48)
|
| ページ |
18421-18433
|
| 公開日 |
2018-11-30
|
| DOI |
10.1074/jbc.RA118.003694
|
| PII |
S0021-9258(20)31153-4
|
| PMID |
30315102
|
| PMC |
PMC6290160
|
| MeSH |
Animals
Disulfides / metabolism
Enzyme Precursors / biosynthesis
Estrogens / metabolism
HeLa Cells
Humans
Male
Mass Spectrometry
Mice
Mice, Inbred C57BL
Pancreas / cytology
Pancreas / enzymology*
Pancreatic Elastase / biosynthesis
Protein Binding
Protein Disulfide-Isomerases / metabolism*
Substrate Specificity
alpha-Amylases / metabolism
|
| IF |
4.238
|
| 引用数 |
3
|
| リソース情報 |
| 遺伝子材料 |
Genome Network Project Human cDNA
IRAL016C10 (HGY086458)
IRAL047P08 (HGY099168) |
