Alterations in nuclear scaffold constituents during carbon tetrachloride–induced liver regeneration

Gary Clawson, Kenneth R. Madsen, Lori J. Blankenship, Christine L. Hatem

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

Liver regeneration was induced in rats by treatment with CCl4, which results in substantial regenerative activity with a sharp mitotic response 2 days after intoxication. Closely paralleling the mitotic index, we observed fourfold increases in nuclear scaffold nucleoside triphosphatase, an activity thought to participate in nucleocytoplasmic RNA transport and in the 46 kD putative enzyme and its selective photolabeling. Because previous work has indicated that the 46 kD protein may be proteolytically derived from lamins A/C by cleavage at a tyrosine residue at aa376, we investigated the response of lamin A/C transcripts during this regeneration. Surprisingly, Northern blot analyses after CCl4 administration showed low levels of lamin A/C transcripts (which appeared to be predominantly poly[A]‐), and we found a decrease in immunoprecipitable lamins A/C from in vitro translation of poly(A)‐selected RNA. To circumvent potential problems with such analyses, we used reverse transcription/polymerase chain reaction amplification of lamin A/C transcripts from total cytoplasmic RNA. These assays showed a transient, comparatively minor increase in lamin A/C transcripts 1 day after treatment, but levels rapidly declined from 1 to 3 days and were decreased at 3 to 5 days. However, nuclear scaffold protease activity, which shows a considerable selectivity for lamins A/C and may be involved in derivation of the 46 kD protein, increased in parallel to the mitotic response and increases in nucleoside triphosphatase, as assessed using a nonspecific (Azocoll) protease assay. Assays with a specific tyrosine‐containing substrate (Z‐Y‐Sbenzyl) showed an increase that mirrored that observed with the nonspecific substrate. Our results suggest that the increases in nuclear scaffold nucleoside triphosphatase activity attendant to nuclear replication appear to result, in large part, from activation of nuclear scaffold proteases. Furthermore, one third to one half of hepatocytes apparently regenerate without any major increase in synthesis of lamins A/C, the major structural proteins of the nuclear scaffold. (HEPATOLOGY 1991;13:515–522.)

Original languageEnglish (US)
Pages (from-to)515-522
Number of pages8
JournalHepatology
Volume13
Issue number3
DOIs
StatePublished - Jan 1 1991

Fingerprint

Lamin Type A
Nuclear Matrix
Liver Regeneration
Carbon
Nucleoside-Triphosphatase
Peptide Hydrolases
RNA Transport
Nuclear Matrix-Associated Proteins
Mitotic Index
Poly A
Cell Nucleus Active Transport
Northern Blotting
Reverse Transcription
Tyrosine
Regeneration
Hepatocytes
Proteins
RNA
Polymerase Chain Reaction
Messenger RNA

All Science Journal Classification (ASJC) codes

  • Hepatology

Cite this

Clawson, Gary ; Madsen, Kenneth R. ; Blankenship, Lori J. ; Hatem, Christine L. / Alterations in nuclear scaffold constituents during carbon tetrachloride–induced liver regeneration. In: Hepatology. 1991 ; Vol. 13, No. 3. pp. 515-522.
@article{2f8451fa7bf440558e576fde4b6059e9,
title = "Alterations in nuclear scaffold constituents during carbon tetrachloride–induced liver regeneration",
abstract = "Liver regeneration was induced in rats by treatment with CCl4, which results in substantial regenerative activity with a sharp mitotic response 2 days after intoxication. Closely paralleling the mitotic index, we observed fourfold increases in nuclear scaffold nucleoside triphosphatase, an activity thought to participate in nucleocytoplasmic RNA transport and in the 46 kD putative enzyme and its selective photolabeling. Because previous work has indicated that the 46 kD protein may be proteolytically derived from lamins A/C by cleavage at a tyrosine residue at aa376, we investigated the response of lamin A/C transcripts during this regeneration. Surprisingly, Northern blot analyses after CCl4 administration showed low levels of lamin A/C transcripts (which appeared to be predominantly poly[A]‐), and we found a decrease in immunoprecipitable lamins A/C from in vitro translation of poly(A)‐selected RNA. To circumvent potential problems with such analyses, we used reverse transcription/polymerase chain reaction amplification of lamin A/C transcripts from total cytoplasmic RNA. These assays showed a transient, comparatively minor increase in lamin A/C transcripts 1 day after treatment, but levels rapidly declined from 1 to 3 days and were decreased at 3 to 5 days. However, nuclear scaffold protease activity, which shows a considerable selectivity for lamins A/C and may be involved in derivation of the 46 kD protein, increased in parallel to the mitotic response and increases in nucleoside triphosphatase, as assessed using a nonspecific (Azocoll) protease assay. Assays with a specific tyrosine‐containing substrate (Z‐Y‐Sbenzyl) showed an increase that mirrored that observed with the nonspecific substrate. Our results suggest that the increases in nuclear scaffold nucleoside triphosphatase activity attendant to nuclear replication appear to result, in large part, from activation of nuclear scaffold proteases. Furthermore, one third to one half of hepatocytes apparently regenerate without any major increase in synthesis of lamins A/C, the major structural proteins of the nuclear scaffold. (HEPATOLOGY 1991;13:515–522.)",
author = "Gary Clawson and Madsen, {Kenneth R.} and Blankenship, {Lori J.} and Hatem, {Christine L.}",
year = "1991",
month = "1",
day = "1",
doi = "10.1002/hep.1840130320",
language = "English (US)",
volume = "13",
pages = "515--522",
journal = "Hepatology",
issn = "0270-9139",
publisher = "John Wiley and Sons Ltd",
number = "3",

}

Alterations in nuclear scaffold constituents during carbon tetrachloride–induced liver regeneration. / Clawson, Gary; Madsen, Kenneth R.; Blankenship, Lori J.; Hatem, Christine L.

In: Hepatology, Vol. 13, No. 3, 01.01.1991, p. 515-522.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Alterations in nuclear scaffold constituents during carbon tetrachloride–induced liver regeneration

AU - Clawson, Gary

AU - Madsen, Kenneth R.

AU - Blankenship, Lori J.

AU - Hatem, Christine L.

PY - 1991/1/1

Y1 - 1991/1/1

N2 - Liver regeneration was induced in rats by treatment with CCl4, which results in substantial regenerative activity with a sharp mitotic response 2 days after intoxication. Closely paralleling the mitotic index, we observed fourfold increases in nuclear scaffold nucleoside triphosphatase, an activity thought to participate in nucleocytoplasmic RNA transport and in the 46 kD putative enzyme and its selective photolabeling. Because previous work has indicated that the 46 kD protein may be proteolytically derived from lamins A/C by cleavage at a tyrosine residue at aa376, we investigated the response of lamin A/C transcripts during this regeneration. Surprisingly, Northern blot analyses after CCl4 administration showed low levels of lamin A/C transcripts (which appeared to be predominantly poly[A]‐), and we found a decrease in immunoprecipitable lamins A/C from in vitro translation of poly(A)‐selected RNA. To circumvent potential problems with such analyses, we used reverse transcription/polymerase chain reaction amplification of lamin A/C transcripts from total cytoplasmic RNA. These assays showed a transient, comparatively minor increase in lamin A/C transcripts 1 day after treatment, but levels rapidly declined from 1 to 3 days and were decreased at 3 to 5 days. However, nuclear scaffold protease activity, which shows a considerable selectivity for lamins A/C and may be involved in derivation of the 46 kD protein, increased in parallel to the mitotic response and increases in nucleoside triphosphatase, as assessed using a nonspecific (Azocoll) protease assay. Assays with a specific tyrosine‐containing substrate (Z‐Y‐Sbenzyl) showed an increase that mirrored that observed with the nonspecific substrate. Our results suggest that the increases in nuclear scaffold nucleoside triphosphatase activity attendant to nuclear replication appear to result, in large part, from activation of nuclear scaffold proteases. Furthermore, one third to one half of hepatocytes apparently regenerate without any major increase in synthesis of lamins A/C, the major structural proteins of the nuclear scaffold. (HEPATOLOGY 1991;13:515–522.)

AB - Liver regeneration was induced in rats by treatment with CCl4, which results in substantial regenerative activity with a sharp mitotic response 2 days after intoxication. Closely paralleling the mitotic index, we observed fourfold increases in nuclear scaffold nucleoside triphosphatase, an activity thought to participate in nucleocytoplasmic RNA transport and in the 46 kD putative enzyme and its selective photolabeling. Because previous work has indicated that the 46 kD protein may be proteolytically derived from lamins A/C by cleavage at a tyrosine residue at aa376, we investigated the response of lamin A/C transcripts during this regeneration. Surprisingly, Northern blot analyses after CCl4 administration showed low levels of lamin A/C transcripts (which appeared to be predominantly poly[A]‐), and we found a decrease in immunoprecipitable lamins A/C from in vitro translation of poly(A)‐selected RNA. To circumvent potential problems with such analyses, we used reverse transcription/polymerase chain reaction amplification of lamin A/C transcripts from total cytoplasmic RNA. These assays showed a transient, comparatively minor increase in lamin A/C transcripts 1 day after treatment, but levels rapidly declined from 1 to 3 days and were decreased at 3 to 5 days. However, nuclear scaffold protease activity, which shows a considerable selectivity for lamins A/C and may be involved in derivation of the 46 kD protein, increased in parallel to the mitotic response and increases in nucleoside triphosphatase, as assessed using a nonspecific (Azocoll) protease assay. Assays with a specific tyrosine‐containing substrate (Z‐Y‐Sbenzyl) showed an increase that mirrored that observed with the nonspecific substrate. Our results suggest that the increases in nuclear scaffold nucleoside triphosphatase activity attendant to nuclear replication appear to result, in large part, from activation of nuclear scaffold proteases. Furthermore, one third to one half of hepatocytes apparently regenerate without any major increase in synthesis of lamins A/C, the major structural proteins of the nuclear scaffold. (HEPATOLOGY 1991;13:515–522.)

UR - http://www.scopus.com/inward/record.url?scp=0025780011&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0025780011&partnerID=8YFLogxK

U2 - 10.1002/hep.1840130320

DO - 10.1002/hep.1840130320

M3 - Article

VL - 13

SP - 515

EP - 522

JO - Hepatology

JF - Hepatology

SN - 0270-9139

IS - 3

ER -