Defective prelamin A processing and muscular and adipocyte alterations in Zmpste24 metalloproteinase–deficient mice

Abstract

The mouse ortholog of human FACE-1, Zmpste24, is a multispanning membrane protein widely distributed in mammalian tissues 1,2 and structurally related to Afc1p/ste24p, a yeast metalloproteinase involved in the maturation of fungal pheromones 3 . Disruption of the gene Zmpste24 caused severe growth retardation and premature death in homozygous-null mice. Histopathological analysis of the mutant mice revealed several abnormalities, including dilated cardiomyopathy, muscular dystrophy and lipodystrophy. These alterations are similar to those developed by mice deficient in A-type lamin 4 , a major component of the nuclear lamina 5 , and phenocopy most defects observed in humans with diverse congenital laminopathies 6-8 . In agreement with this finding, Zmpste24-null mice are defective in the proteolytic processing of prelamin A. This deficiency in prelamin A maturation leads to the generation of abnormalities in nuclear architecture that probably underlie the many phenotypes observed in both mice and humans with mutations in the lamin A gene. These results indicate that prelamin A is a specific substrate for Zmpste24 and demonstrate the usefulness of genetic approaches for identifying the in vivo substrates of proteolytic enzymes.To clarify the function of Zmpste24, and to identify in vivo substrates targeted by this proteinase, we generated Zmpste24-null mice (Fig. 1a). After heterozygote intercrossing, we obtained Zmpste24-null, heterozygous and wildtype mice in the expected mendelian ratio. We verified homozygosity with respect to the mutated allele by Southern blot (Fig. 1b), and lack of Zmpste24 Fig. 1 Generation of Zmpste24-deficient mice. a, Schematic representation of the wildtype Zmpste24 locus (WT), targeting vector and targeted allele (KO). Positions of restriction enzyme sites and probes used for Southern-blot analysis are shown. b, Southern-blot analysis of genomic DNA from three littermate progeny of Zmpste24 heterozygote crosses. Probing of EcoRI-digested DNA revealed fragments of 6 kb and 4 kb for wildtype and disrupted alleles, respectively. Probing of BamHI-digested DNA revealed fragments of 10 kb and 8 kb for wildtype and disrupted alleles, respectively. c, Extracts of kidneys from wildtype and Zmpste24 -/-mice were examined with a monoclonal antibody directed against the C terminus of Zmpste24. d, Photograph of two littermate progeny of a Zmpste24 heterozygote cross, at 3 mo. e, Radiograph of a Zmpste24 -/-mouse at 3 mo, compared with a wildtype control. f, Cumulative plot of body weight versus age. Dots represent mean values, and error bars indicate s.e.m.

Changes at the nuclear lamina alter binding of pioneer factor Foxa2 in aged liver

“…Hepatic steatosis is a common phenotype for aged mice (Jin et al., 2010; Ogrodnik et al., 2017), Zmpste24 mutants (Marino et al., 2008; Pendas et al., 2002), and liver‐specific Lmna knockouts (Kwan et al., 2017). In addition, mutations in LMNA and ZMPSTE24 in patients lead to metabolic dysfunction, including type 2 diabetes and hepatic steatosis (Galant et al., 2016; Shackleton et al., 2000).…”

Accelerated ageing: from mechanism to therapy through animal models

“…Accordingly, Face-1/Zmpste24-deficient mice accumulate farnesylated prelamin A at the nuclear envelope and phenocopy human HGPS, providing a valuable animal model for the study of this pathology (Pendas et al 2002;Bergo et al 2002;Cadinanos et al 2005;de Carlos et al 2008). Using transcriptional profiling on tissues from this knockout model, we found that hyperactivation of p53 signalling plays a key role in the accelerated ageing phenotype, which is partially reversed by p53 deficiency .…”

“…To investigate the biological roles of this enzyme, we used gene targeting to generate Zmpste24 -/-mice (Pendas et al 2002). Zmpste24-deficient mice are apparently normal at birth, but they show a striking accumulation of prelamin A at the nuclear envelope, which leads to frequent nuclear abnormalities at the cellular level.…”

“…The use of genetically modified mice allowed us to identify the zinc metalloprotease FACE-1 (also known as ZMPSTE24) as the enzyme responsible for the final proteolytic step during lamin A posttranslational maturation (Pendas et al 2002). Accordingly, Face-1/Zmpste24-deficient mice accumulate farnesylated prelamin A at the nuclear envelope and phenocopy human HGPS, providing a valuable animal model for the study of this pathology (Pendas et al 2002;Bergo et al 2002;Cadinanos et al 2005;de Carlos et al 2008).…”

MicroRNAs in hereditary and sporadic premature aging syndromes and other laminopathies

“…Depending on the implicated mutation, a farnesylated truncated or wild‐type full prelamin A accumulates in nuclei (Navarro et al., 2004). The Zmpste24 ‐deficient mouse model (Zmpste24 −/− ) presents severe growth retardation and premature death associated with cardiomyopathy, muscular dystrophy, and lipodystrophy (Pendás et al., 2002). In these mice, farnesylated prelamin A accumulates, as expected, but the phenotype corresponds to human HGPS rather than restrictive dermopathy.…”