Agouti signaling protein stimulates cell division in "viable yellow" (A(vy)/a) mouse liver.

Abstract

Enhanced linear growth, hyperplasia, and tumorigenesis are well-known characteristics of "viable yellow" agouti A(vy)/- mice (Wolff GL, Roberts DW, Mountjoy KG. Physiol Genomics 1:151-163, 1999); however, the functional basis for this aspect of the phenotype is unknown. In the present study, we ascertained whether agouti signaling protein (ASIP) levels in A(vy)/a or a/a livers are associated with hepatocyte proliferation as a possible factor in promotion of hepatocellular tumor formation. Proliferating cell nuclear antigen (PCNA) assays and quantitative real-time reverse transcriptase polymerase chain reaction assays were performed on liver samples from mottled yellow A(vy)/a, pseudoagouti A(vy)/a, and black a/a VY mice to determine mitotic indices and expression levels of A(vy )and a in relation to the expression level of the housekeeping gene hprt. We found that ASIP levels were approximately 100-fold higher in yellow than in pseudoagouti or black mice and that the proportion of PCNA-positive hepatocytes was greater (P < 0.001) in yellow than in pseudoagouti or black mice.

• Authors: George L Wolff, J Steven Stanley, Matthew E Ferguson, Pippa M Simpson, Martin J J Ronis, Thomas M Badger
• Journal: Experimental biology and medicine (Maywood, N.J.) (Exp Biol Med (Maywood)) Vol. 232 Issue 10 Pg. 1326-9 (Nov 2007) ISSN: 1535-3702 [Print] England
• PMID: 17959845 (Publication Type: Journal Article, Research Support, U.S. Gov't, Non-P.H.S.)

Chemical References

• Agouti Signaling Protein
• Proliferating Cell Nuclear Antigen

Topics

• Agouti Signaling Protein (genetics, physiology)
• Animals
• Cell Division (physiology)
• Hepatocytes (physiology)
• Liver (cytology)
• Mice
• Mice, Mutant Strains
• Proliferating Cell Nuclear Antigen (analysis)
• Reverse Transcriptase Polymerase Chain Reaction