Hepatic glutaminase mRNA is confined to part of the urea cycle domain in the adult rodent liver lobule

FEBS Letters

Moorman, Antoon F.M.²  Lamers, Wouter H.²  de Boer, Pict A.J.²  Watford, Malcolm¹  Dingemanse, Maria A.² 

[1] Department of Nutritional Sciences, Cook College, Rutgers, The State University, New Brunswick, NJ 08903, USA;Academic Medical Center, University of Amsterdam, Department of Anatomy and Embryology, Meibergdreef 15, 1105 AZ Amsterdam, The Netherlands

关键词: Glutaminase;    In situ hybridization;    Liver;    Urea cycle;   

DOI  :  10.1016/0014-5793(94)01230-X

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

This in situ hybridization study describes the developmental appearance of the lobular distribution of the mRNA encoding hepatic glutaminase in normal rat liver. Glutaminase has been proposed to provide the urea cycle with ammonia [Hässinger and Gerok (1983) Eur. J. Biochem. 133, 269–275]. Hence, the (developmental) pattern of expression of the mRNA would be expected to be closely linked to that of the urea cycle enzymes. From embryonic day 20 onward, hepatic glutaminase mRNA can be detected along the entire porto-central axis, with predominant expression in the portal area. In the adult phenotype, which is acquired at the end of the first postnatal week, glutaminase mRNA is no longer present along the entire porto-central distance but has become confined to a relatively small periportal domain in which the expression decreases in a porto-central direction. Thus, in contrast to the large periportal domain, in which the urea cycle enzymes are expressed, the glutaminase mRNA-expressing domain is much smaller and not contiguous with the glutamine synthase mRNA-expressing pericentral domain, leaving a midlobular area that is devoid of glutaminase mRNA. A similar pattern of distribution was found in adult mouse liver. The significance of these observations is that, within the liver lobules, there is an area in which glutaminase is not expressed and, hence, glutamine can not be the substrate for urea synthesis.

【 授权许可】

Unknown