Elsevier

Gene

Volume 291, Issues 1–2, 29 May 2002, Pages 29-34
Gene

Isolation, characterization and mapping of the mouse and human RB1CC1 genes

https://doi.org/10.1016/S0378-1119(02)00585-1Get rights and content

Abstract

RB1CC1 (RB1-inducible Coiled-Coil 1), a putative transcription factor implicated in the regulation of RB1 (retinoblastoma 1) expression, was recently identified in a screen for genes involved in multi-drug resistance to anticancer agents. Information about the RB1CC1 gene is limited, however, and its biological function is not determined. Here we report the isolation, characterization and mapping of the mouse RB1CC1 gene (Rb1cc1), together with further characterization of the human RB1CC1 gene. Mouse Rb1cc1 encodes 1588 amino acids, sharing 89% identity and key sequence motifs with its human counterpart. Rb1cc1 is expressed abundantly in heart and testis, with lower levels detected in lung and spleen. Immunohistochemical analysis revealed the Rb1cc1 and Rb1 proteins are co-localized in the cell nuclei of NIH3T3-3 cell and various mouse tissues. The human and mouse RB1CC1 genes, both of which contain 24 exons, span 74 kb on chromosome 8q11.2 and 57 kb on chromosome 1A2–4, respectively. Conserved sequence motifs and nuclear localization suggest that the RB1CC1 proteins function as transcription factors.

Introduction

We recently identified a novel human gene, RB1CC1 (RB1-inducible Coiled-Coil 1: Human Gene Nomenclature Committee-approved gene symbol), during a search for genes implicated in multi-drug resistance (MDR) to anticancer agents (Chano et al., 2002). RB1CC1 expression is associated with the survival of MDR cancer cells treated with anticancer agents. Preliminary experiments also suggest that RB1CC1 may function as a key regulator for RB1 (retinoblastoma 1) expression: RB1CC1 expression correlates closely with that of RB1 in various cancer cell lines and normal human tissues, and introduction of wild-type RB1CC1 induced significant RB1 expression in human leukemic cells (Chano et al., 2002).

Two previous studies have independently identified mouse Rb1cc1 as a cytoplasmic protein with varied functions, however. Maucuer et al. (1995) called Rb1cc1 as Cc1, and reported that it interacts with stathmin, a ubiquitous cytoplasmic protein, and predicted that Cc1 responds to many regulatory signals through its interaction with stathmin. Pfeuffer et al. (2000) called it as LaXp180, and proposed that it binds to the Listeria monocytegenes surface protein ActA, an important virulence factor, in listeriae-infected mammalian cells. These results contradict to our recent study in human. The deduced amino acid sequence of RB1CC1 contains a nuclear localization signal, a leucine zipper motif and a coiled-coil structure, indicating RB1CC1 is a nuclear protein; Immunoblot and immunocytochemical analyses have demonstrated nuclear localization of the human RB1CC1 protein (Chano et al., 2002). It remains to be determined whether the contradiction may result from species difference, or multiple function of RB1CC1; however, clarification of the molecular roles of RB1CC1 is hampered by scarcity of information about the gene. To gain more insight into RB1CC1 function, we have further characterized the human and mouse RB1CC1 genes.

Section snippets

Rb1cc1 cDNA isolation and sequencing

To clone the complete mouse Rb1cc1 cDNA, we performed a BLAST homology search of public databases using the human RB1CC1 cDNA sequence (GenBank accession no. AB059622) as query sequence. Several mouse clones (accession nos. AW495435, AA497846, AJ242720, AA458361, AW701067) were identified, and primers were designed based on their sequences. cDNAs were synthesized by RT–PCR, using oligo (dT)12–18 primer and C57BL/6 mouse muscle mRNA. The entire Rb1cc1 coding region was amplified using the

Rb1cc1 is the mouse homologue of human RB1CC1

The complete Rb1cc1 cDNA was 6518 bp in length with an open leading frame of 4764 bp, coding 1588 amino acids (accession no. AB070619). The clone was considered to contain a full-length cDNA because: (1) the putative transcription start sites and first methionine were good alignment with its human counterpart RB1CC1; (2) sequence around the putative translation start site (ATC ATC ATG A) was compatible with the Kozak consensus; (3) repeated attempts of 5′-RACE did not yield more 5′ clones; and

Acknowledgements

This study was partially supported by grants-in-aid for JSPS Fellows (No. 4808), Scientific Research (B) (No. 13470520), The Ministry of Education, Science, Sports and Culture of Japan, and a grant from the Japan Orthopaedics and Traumatology Foundation, Inc. (No. 0110).

References (6)

There are more references available in the full text version of this article.

Cited by (15)

  • Autophagy as a molecular target for cancer treatment

    2019, European Journal of Pharmaceutical Sciences
  • RB1CC1 protein positively regulates transforming growth factor-β signaling through the modulation of Arkadia E3 ubiquitin ligase activity

    2011, Journal of Biological Chemistry
    Citation Excerpt :

    Although RB1CC1 appears to be dispensable for the regulation of Smad signaling during early embryonic development, it may play a role in adults. The RB1CC1 gene is located in chromosome 8q11, which contains several loci of putative tumor suppressor genes (43, 63). RB1CC1 potently inhibits proliferation of breast cancer cells through up-regulation of p21WAF (53, 64), p16INK4a, and RB1 (64) as well as down-regulation of cyclin D (53).

  • FIP200, a key signaling node to coordinately regulate various cellular processes

    2008, Cellular Signalling
    Citation Excerpt :

    FIP200 also contains a putative nuclear localization signal (NLS), suggesting that it might localize in nucleus (Fig. 1). Human and mouse FIP200 proteins share around 90% identity and similar domain structure [8]. FIP200 is an evolutionarily conserved protein present in human, mouse, rat, Xenopus laevis, Drosophila melanogaster and Caenorhabditis elegans.

  • RB1CC1 insufficiency causes neuronal atrophy through mTOR signaling alteration and involved in the pathology of Alzheimer's diseases

    2007, Brain Research
    Citation Excerpt :

    RB1CC1 is ubiquitously expressed in the developing mouse embryos (Bamba et al., 2004; Watanabe et al., 2005), and the findings in RB1CC1 KO embryos confirmed that RB1CC1 plays an essential and important role in cell size control and survival during embryogenesis, especially in the development of heart and liver (Gan et al., 2006). RB1CC1 is abundantly expressed in neuromuscular tissues of mature adults (Chano et al., 2002a,c, 2006), suggesting its essential role in mature tissue organization. Analysis of disorders in RB1CC1 molecular cascades in the degenerative diseases of adult onset is quite important to elucidate its fundamental role in the adult tissue and to find out novel aspects of such diseases to create new therapeutic approaches.

View all citing articles on Scopus
View full text