C-terminal fragments of parathyroid hormone-related protein, PTHrP-(107-111) and (107-139), and the N-terminal PTHrP-(1-40) fragment stimulate membrane-associated protein kinase C activity in rat spleen lymphocytes.
Membrane-associated protein kinase C (PKC) activity in lymphocytes freshly isolated from rat spleen was stimulated by the C-terminal parathyroid hormone-related protein fragments, PTHrP-(107-111) and PTHrP-(107-139), at concentrations from 10(-3) to 10(4) pM. By contrast, the same concentrations of PTHrP-(120-139), without the 107-111 TRSAW (-Thr-Arg-Ser-Ala-Trp-) sequence of the other C terminal fragments, did not stimulate spleen lymphocyte PKC. Low concentrations of the N-terminal PTHrP-(1-40) fragment also stimulated membrane-associated PKC activity in the spleen lymphocytes. These results suggest that PTHrP might be an important physiological regulator of the immune response.
Whitfield
J F
JF
Cell Systems Section, National Research Council of Canada, Ottawa, Ontario.
Isaacs
R J
RJ
Chakravarthy
B R
BR
Durkin
J P
JP
Morley
P
P
Neugebauer
W
W
Williams
R E
RE
Willick
G
G
Rixon
R H
RH
D000818:Animals; D002455:Cell Division; D002462:Cell Membrane / Q000201:enzymology / Q000648:ultrastructure; D002478:Cells, Cultured; D002851:Chromatography, High Pressure Liquid; D004789:Enzyme Activation; D008214:Lymphocytes / Q000166:cytology* / Q000201:enzymology* / Q000648:ultrastructure; D008297:Male; D044162:Parathyroid Hormone-Related Protein; D010446:Peptide Fragments / Q000494:pharmacology*; D011493:Protein Kinase C / Q000378:metabolism* / Q000502:physiology; D011506:Proteins / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013154:Spleen / Q000166:cytology* / Q000201:enzymology* / Q000648:ultrastructure
D044162:Parathyroid Hormone-Related Protein; D010446:Peptide Fragments; D011506:Proteins; C071784:parathyroid hormone-related protein (107-111); C071097:parathyroid hormone-related protein (107-139); D011493:Protein Kinase C