Humanizing mouse folate metabolism: conversion of the dual-promoter mouse folylpolyglutamate synthetase gene to the human single-promoter structure.
FASEB J
; 28(5): 1998-2008, 2014 May.
Article
em En
| MEDLINE
| ID: mdl-24532667
The mouse is extensively used to model human folate metabolism and therapeutic outcomes with antifolates. However, the folylpoly-γ-glutamate synthetase (fpgs) gene, whose product determines folate/antifolate intracellular retention and antifolate antitumor activity, displays a pronounced species difference. The human gene uses only a single promoter, whereas the mouse uses two: P2, akin to the human promoter, at low levels in most tissues; and P1, an upstream promoter used extensively in liver and kidney. We deleted the mouse P1 promoter through homologous recombination to study the dual-promoter mouse system and to create a mouse with a humanized fpgs gene structure. Despite the loss of the predominant fpgs mRNA species in liver and kidney (representing 95 and 75% of fpgs transcripts in these tissues, respectively), P1-knockout mice developed and reproduced normally. The survival of these mice was explained by increased P2 transcription due to relief of transcriptional interference, by a 3-fold more efficient translation of P2-derived than P1-derived transcripts, and by 2-fold higher stability of P2-derived FPGS. In combination, all 3 effects reinstated FPGS function, even in liver. By eliminating mouse P1, we created a mouse model that mimicked the human housekeeping pattern of fpgs gene expression.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Peptídeo Sintases
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Regiões Promotoras Genéticas
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Ácido Fólico
Limite:
Animals
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Humans
Idioma:
En
Ano de publicação:
2014
Tipo de documento:
Article