Characterization of Expression in Mice of a Transgene Containing 3.3 kb of the Human Lactase-Phlorizin Hydrolase (LPH) 50 Flanking Sequence
- نوع فایل : کتاب
- زبان : انگلیسی
- مؤلف : Nana Yaa Baffour-Awuah Eveline Delemarre Yuko Fujiwara Jarom Heijmans David Boerwinkel Selma Algra John J. Fialkovich Shabana Islam T
- چاپ و سال / کشور: 2010
Description
Background and Aim The regulation of human intestinal lactase-phlorizin hydrolase remains incompletely understood. One kb of pig and 2 kb of rat 50-flanking sequence controls correct tissue, cell, topographic, and villus LCT expression. To gain insight into human LCTexpression, transgenicmouse lines were generated from 3.3 kb of human LPH 50 flanking sequence froma lactase persistent individual fused to a human growth hormone (hGH) reporter bounded by an insulator. Methods Four lines were identified in which reporter expression was specifically detectable in the intestine and no other organ, two of which demonstrated hGH expression specific to small and large intestine. Quantitative RT-PCR was carried out on proximal to distal segments of small intestine at fetal days 16.5 and 18.5 and at birth, postnatal days 7 and 28 in line 22. Results In fetal intestine, hGH expression demonstrated a proximal to distal gradient similar to that in native intestine. There was no significant difference between hGH expression levels at 7 and 28 days in segment 3, the midpoint of the small intestine, where expression of endogenous lactase is maximal at 7 days and declines significantly by 28 days. Distal small intestine displayed high levels of hGH expression in enteroendocrine cells, which were shown to be a subset of the PYY cells. Conclusions Thus, a 3.3-kb LPH 50 flanking sequence construct from a lactase persistent individual is able to maintain postnatal expression in transgenic mice post weaning.
Dig Dis Sci (2011) 56:59–69 DOI 10.1007/s10620-010-1480-2 Received: 28 May 2010 / Accepted: 26 October 2010 / Published online: 18 November 2010
