Generation and identification of a conditional knockout allele for the PSMD11 gene in mice

Linlin Zhao,Lele Wang,Suhong Zhao,Longyan Zuo,Chuanxin Wang,Dieter Saur,Tonggang Qi,Chao Sun,Jue Wang,Jinming Zhao,Zhimin Bian,Xia Xue,Kailin Li,Wei Zhang,Yingying Zhang,Xiaogang Zhao,Barbara Seidler,Airu Niu

doi:10.1186/s12861-020-00233-1

Abstract

BackgroundOur previous study have shown that the PSMD11 protein was an important survival factor for cancer cells except for its key role in regulation of assembly and activity of the 26S proteasome. To further investigate the role of PSMD11 in carcinogenesis, we constructed a conditional exon 5 floxed allele of PSMD11 (PSMD11flx) in mice.ResultsIt was found that homozygous PSMD11 flx/flx mice showed normal and exhibited a normal life span and fertility, and showed roughly equivalent expression of PSMD11 in various tissues, suggesting that the floxed allele maintained the wild-type function. Cre recombinase could induce efficient knockout of the floxed PSMD11 allele both in vitro and in vivo. Mice with constitutive single allele deletion of PSMD11 derived from intercrossing between PSMD11flx/flx and CMV-Cre mice were all viable and fertile, and showed apparent growth retardation, suggesting that PSMD11 played a significant role in the development of mice pre- or postnatally. No whole-body PSMD11 deficient embryos (PSMD11−/−) were identified in E7.5–8.5 embryos in uteros, indicating that double allele knockout of PSMD11 leads to early embryonic lethality. To avoid embryonic lethality produced by whole-body PSMD11 deletion, we further developed conditional PSMD11 global knockout mice with genotype Flp;FSF-R26CAG − CreERT2/+; PSMD11flx/flx, and demonstrated that PSMD11 could be depleted in a temporal and tissue-specific manner. Meanwhile, it was found that depletion of PSMD11 could induce massive apoptosis in MEFs.ConclusionsIn summary, our data demonstrated that we have successfully generated a conditional knockout allele of PSMD11 in mice, and found that PSMD11 played a key role in early and postnatal development in mice, the PSMD11 flx/flx mice will be an invaluable tool to explore the functions of PSMD11 in development and diseases.

Highlights

Our previous study have shown that the Proteasome s subunit (PSMD11) protein was an important survival factor for cancer cells except for its key role in regulation of assembly and activity of the 26S proteasome
In order to understand the role of proteasome in these diseases, knockout studies for several subunits of proteasome have been conducted in mice, including Psmc3 and Psmc4 [9], Psmc1 [10], and Psmd4 [11], and found that proteasome play an indispensable role in early-embryonic development of mice and pathogenesis of some of the neurodegenerative diseases [10, 12]
Construction and identification of a conditional floxed allele of PSMD11 in mice The murine PSMD11 gene, about 44.62 kb in length, is situated on the reverse strand of chromosome 11, and consists of 14 exons in which the ATG start codon is in exon 1 and TAG stop codon in exon 13 (Fig. 1a)

Summary

Introduction

Our previous study have shown that the PSMD11 protein was an important survival factor for cancer cells except for its key role in regulation of assembly and activity of the 26S proteasome. In order to understand the role of proteasome in these diseases, knockout studies for several subunits of proteasome have been conducted in mice, including Psmc and Psmc4 [9], Psmc1 [10], and Psmd4 [11], and found that proteasome play an indispensable role in early-embryonic development of mice and pathogenesis of some of the neurodegenerative diseases [10, 12]. The PSMD11 (Proteasome 26 s subunit, non-ATPase, 11) protein ( known as RPN-6 in Caenorhabditis elegans) [13,14,15] is a component of the lid of the 19S RP, and plays a key role in the regulation of assembly and activity of the 26S proteasome [16, 17]. Quick degradation of PSMD11 protein has been found to be associated with acute apoptosis in cancer cells, and its knockdown by siRNA can promote acute apoptosis in pancreatic cancer cells [18], suggesting that PSMD11 may be a multifunctional protein, and may be a novel therapeutic target for cancer, whether it can be targeted to treat cancer deserve further investigation

Results

Discussion

Conclusion