A liver specific gene that is expressed in growth hormone transgenic mice and in normal female mice as a function of age

TY - JOUR

T1 - A liver specific gene that is expressed in growth hormone transgenic mice and in normal female mice as a function of age

AU - Tiong, Jean D R

AU - Gosney, Elahu

AU - Ding, Juan

AU - Chin, Edward

AU - Kopchick, John J.

PY - 2006/6/1

Y1 - 2006/6/1

N2 - Growth hormone (GH) acts on various organs to exert its growth and metabolic effects. GH induces transcription of a number of genes in different organs including liver. By performing subtractive hybridization analysis on liver cDNAs of GH transgenic and non-transgenic mice, differentially expressed cDNAs were obtained. This paper describes the isolation and characterization of a liver cDNA, termed cDNA #5, that contains 1897 bp and is predicted to encode a protein (P5) of 512 aa residues. P5 has five immunoglobulin related domains thus allowing it to be classified as a member of the immunoglobulin super family (IGSF). Also, P5 shows significant similarity to both rat and human alpha-1-B glycoprotein which is an acidic serum protein of unknown function. mRNA #5 was detected in the liver hepatocytes of male and female GH transgenic mice and in the liver of female, but not of male, non-transgenic mice. mRNA #5 was not present in dwarf mice including the Ames dwarf, those that express a GH antagonist and those with the GH receptor and binding protein gene disrupted. These findings suggest that induction of mRNA #5 in the liver requires a continuous pattern of GH secretion and an intact GH-GH receptor-signaling complex. mRNA #5 levels in female non-transgenic mice were observed to vary with age implying that gender-specific age-dependent factor(s) may be involved in the induction of mRNA #5. The appearance of mRNA #5 in post-hepatectomized liver that coincides with the proliferative phase of liver regeneration suggests that it may be involved in hepatocyte proliferation. Together these data suggest that expression of cDNA #5 is liver-specific, sexually dimorphic, age-dependent, and may be involved in hepatocyte hyperplasia and liver enlargement.

AB - Growth hormone (GH) acts on various organs to exert its growth and metabolic effects. GH induces transcription of a number of genes in different organs including liver. By performing subtractive hybridization analysis on liver cDNAs of GH transgenic and non-transgenic mice, differentially expressed cDNAs were obtained. This paper describes the isolation and characterization of a liver cDNA, termed cDNA #5, that contains 1897 bp and is predicted to encode a protein (P5) of 512 aa residues. P5 has five immunoglobulin related domains thus allowing it to be classified as a member of the immunoglobulin super family (IGSF). Also, P5 shows significant similarity to both rat and human alpha-1-B glycoprotein which is an acidic serum protein of unknown function. mRNA #5 was detected in the liver hepatocytes of male and female GH transgenic mice and in the liver of female, but not of male, non-transgenic mice. mRNA #5 was not present in dwarf mice including the Ames dwarf, those that express a GH antagonist and those with the GH receptor and binding protein gene disrupted. These findings suggest that induction of mRNA #5 in the liver requires a continuous pattern of GH secretion and an intact GH-GH receptor-signaling complex. mRNA #5 levels in female non-transgenic mice were observed to vary with age implying that gender-specific age-dependent factor(s) may be involved in the induction of mRNA #5. The appearance of mRNA #5 in post-hepatectomized liver that coincides with the proliferative phase of liver regeneration suggests that it may be involved in hepatocyte proliferation. Together these data suggest that expression of cDNA #5 is liver-specific, sexually dimorphic, age-dependent, and may be involved in hepatocyte hyperplasia and liver enlargement.

KW - Aging

KW - Alpha-1B-glycoprotein

KW - GH

KW - GH transgenic mice

KW - GH-regulated genes

KW - Immunoglobulin super family

KW - Liver regeneration

KW - Sexual dimorphism

KW - Subtractive cDNA hybridization

UR - http://www.scopus.com/inward/record.url?scp=33746291097&partnerID=8YFLogxK

U2 - 10.1016/j.ghir.2006.03.011

DO - 10.1016/j.ghir.2006.03.011

M3 - Journal article

C2 - 16723264

AN - SCOPUS:33746291097

SN - 1096-6374

VL - 16

SP - 145

EP - 156

JO - Growth Hormone & I G F Research

JF - Growth Hormone & I G F Research

IS - 3

ER -