|
J. Biol. Chem., Vol. 261, Issue 15, 6853-6859, May, 1986
Regulation of catabolism of microinjected ribonuclease A. Identification of residues 7-11 as the essential pentapeptide [published erratum appears in J Biol Chem 1986 Oct 5;261(28):13387]
JF Dice, HL Chiang, EP Spencer and JM Backer
We have identified a pentapeptide region of microinjected ribonuclease A
that is required for enhanced degradation of this protein during serum
withdrawal. We introduced reductively methylated [3H]ribonuclease A,
[3H]ribonuclease S-protein (residues 21-124), and [3H]ribonuclease S-
peptide (residues 1-20) into the cytosol of human fibroblasts by red
cell-mediated microinjection and osmotic lysis of pinosomes. The
degradative rates of ribonuclease A and ribonuclease S-peptide are
increased 2-fold upon withdrawal of serum, while catabolism of ribonuclease
S-protein is not regulated in this manner. Certain fragments of
ribonuclease S-peptide are also degraded in a serum- dependent fashion
(residues 1-14 and 4-13), while other fragments are not (residues 1-10 and
2-8). [3H]Ribonuclease S-peptide is cleaved into two smaller radioactive
peptides during loading into red cell ghosts. We tentatively identified the
larger fragment as residues 7-11 based on its molecular weight determined
by Sephadex chromatography in the presence of 8 M urea combined with
sequential Edman degradation to identify the position of radioactive
lysines. The smaller peptide fragment appears to be the amino-terminal
dipeptide, Lys-Glu, and/or residues 7-8, Lys-Phe. After microinjection into
fibroblasts, the pentapeptide is degraded at an enhanced rate in the
absence of serum, while degradation of the dipeptide is not affected. We
confirmed that residues 7-11 constitute the larger hydrolysis product of
S-peptide by synthesizing this pentapeptide and radiolabeling it by
reductive methylation. It migrated at the expected position after Sephadex
chromatography in 8 M urea and was further hydrolyzed only slightly during
loading into red cells. Finally, degradation of this pentapeptide after
injection into fibroblasts was enhanced 2-fold upon serum withdrawal. These
results, combined with our other recent studies (McElligott, M. A., Miao,
P., and Dice, J. F. (1985) J. Biol. Chem. 260, 11986-11993), suggest that
the pentapeptide, Lys-Phe-Glu-Arg-Gln, targets microinjected ribonuclease A
to lysosomes for enhanced degradation during serum deprivation.

CiteULike Complore Connotea Del.icio.us Digg Reddit Technorati What's this?
This article has been cited by other articles:

|
 |

|
 |
 
P. F. Finn and J. F. Dice
Ketone Bodies Stimulate Chaperone-mediated Autophagy
J. Biol. Chem.,
July 8, 2005;
280(27):
25864 - 25870.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. C. Haigis, E. L. Kurten, R. L. Abel, and R. T. Raines
KFERQ Sequence in Ribonuclease A-mediated Cytotoxicity
J. Biol. Chem.,
March 22, 2002;
277(13):
11576 - 11581.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
N. Vitale, V. J. Ferrans, J. Moss, and M. Vaughan
Identification of Lysosomal and Golgi Localization Signals in GAP and ARF Domains of ARF Domain Protein 1
Mol. Cell. Biol.,
October 1, 2000;
20(19):
7342 - 7352.
[Abstract]
[Full Text]
|
 |
|

|
 |

|
 |
 
F. A. Agarraberes, S. R. Terlecky, and J. F. Dice
An Intralysosomal hsp70 Is Required for a Selective Pathway of Lysosomal Protein Degradation
J. Cell Biol.,
May 19, 1997;
137(4):
825 - 834.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
A. M. Cuervo, J. F. Dice, and E. Knecht
A Population of Rat Liver Lysosomes Responsible for the Selective Uptake and Degradation of Cytosolic Proteins
J. Biol. Chem.,
February 28, 1997;
272(9):
5606 - 5615.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
H. Chiang, Terlecky SR, C. Plant, and J. Dice
A role for a 70-kilodalton heat shock protein in lysosomal degradation of intracellular proteins
Science,
October 20, 1989;
246(4928):
382 - 385.
[Abstract]
[PDF]
|
 |
|
Copyright © 1986 by the American Society for Biochemistry and Molecular Biology.
|
Advertisement
Advertisement
|