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The Adult Murine Intestine is Dependent on Constitutive Laminin-?1 Synthesis.

ABSTRACT: Laminin-?1 is required for early embryonic development; however, the need for laminin-?1 synthesis in adulthood is unknown. A global and inducible mouse model of laminin-?1 deficiency was generated to address this question. Genetic ablation of the Lamc1 gene in adult mice was rapidly lethal. Despite global Lamc1 gene deletion in tamoxifen-induced mutant mice, there was minimal change in total cardiac, pulmonary, hepatic or renal laminin protein. In contrast, laminin-?1 was significantly depleted in the small intestines, which showed crypt hyperplasia and dissociation of villous epithelium from adjacent mesenchyme. We conclude that the physiologic requirement for laminin-?1 synthesis in adult mice is dependent on a tissue-specific basal rate of laminin-?1 turnover that results in rapid depletion of laminin-?1 in the intestine.

SUBMITTER: Fields B

PROVIDER: S-EPMC6917708 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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The Adult Murine Intestine is Dependent on Constitutive Laminin-γ1 Synthesis.

Fields British B DeLaForest Ann A Zogg Mark M May Jennifer J Hagen Catherine C Komnick Kristin K Wieser Jon J Lundberg Alexander A Weiler Hartmut H Battle Michele A MA Carlson Karen-Sue KS

Scientific reports 20191217 1

Laminin-γ1 is required for early embryonic development; however, the need for laminin-γ1 synthesis in adulthood is unknown. A global and inducible mouse model of laminin-γ1 deficiency was generated to address this question. Genetic ablation of the Lamc1 gene in adult mice was rapidly lethal. Despite global Lamc1 gene deletion in tamoxifen-induced mutant mice, there was minimal change in total cardiac, pulmonary, hepatic or renal laminin protein. In contrast, laminin-γ1 was significantly depleted ...[more]

PMID: 31848396

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