Characterization of the mouse Abcc12 gene and its transcript encoding an ATP-binding cassette transporter, an orthologue of human ABCC12☆
Introduction
The ATP-binding cassette (ABC) transporters form one of the largest protein families and play a biologically important role as membrane transporters or ion channel modulators (Higgins, 1992). According to the recently published draft sequence of the human genome, more than 50 human ABC transporter genes (including pseudogenes1) are anticipated to exist in the human genome. Hitherto 49 human ABC-transporter genes have been identified and sequenced (recent reviews: Klein et al., 1999, Dean et al., 2001, Borst and Oude Elferink, 2002). Based on the arrangement of their molecular structural components, i.e. the nucleotide binding domain and the topology of transmembrane spanning domains, human ABC transporters are classified into seven different gene families designated as A to G (the new nomenclature of human ABC transporter genes: http://gene.ucl.ac.uk/nomenclature/genefamily/abc.html). Mutations in the human ABC transporter genes have been reported to cause such genetic diseases as Tangier disease, cystic fibrosis, Dubin–Johnson syndrome, Stargardt disease, and sitosterolemia (recent reviews: Dean et al., 2001, Borst and Oude Elferink, 2002).
We originally reported that transport of glutathione S-conjugates and leukotriene C4 (LTC4) across the cell membrane is mediated by an ATP-dependent transporter named the ‘GS-X pump’ (Ishikawa, 1989, Ishikawa, 1992); however, the molecular nature of the transporter was not uncovered at that time. Later studies have provided evidence that the GS-X pump is encoded, at least, by the ABCC1 (MRP1) gene (Leier et al., 1994, Müller et al., 1994). ABCC1 (MRP1) was first identified by Cole et al. (1992) in the molecular cloning of cDNA from human multidrug-resistant lung cancer cells. After the discovery of the ABCC1 (MRP1) gene, six human homologues, ABCC2 (cMOAT/MRP2), ABCC3 (MRP3), ABCC4 (MRP4), ABCC5 (MRP5), ABCC6 (MRP6), and ABCC10 (MRP7) have been successively identified. Those ABC transporters exhibit a wide spectrum of biological functions and are involved in the transport of drugs as well as endogenous substances (see recent reviews: Borst and Oude Elferink, 2002, Ishikawa, in press).
Most recently, our group (Yabuuchi et al., 2001) and others (Tammur et al., 2001, Bera et al., 2001, Bera et al., 2002) have independently discovered two novel ABC transporters, human ABCC11 (MRP8) and ABCC12 (MRP9), that belong to the ABCC gene family. The predicted amino acid sequences of both gene products show a high similarity with ABCC5. The ABCC11 and ABCC12 genes consist of at least 30 and 29 exons, respectively, and they are tandemly located in a tail-to-head orientation on human chromosome 16q12.1 (Yabuuchi et al., 2001, Tammur et al., 2001). The physiological functions of these genes are not yet known; however recent linkage analyses have demonstrated that a putative gene responsible for paroxysmal kinesigenic choreoathetosis (PKC), a genetic disease of infancy, is located in the region of 16p11.2–q12.1 (Lee et al., 1998, Tomita et al., 1999). Since the ABCC11 and ABCC12 genes are encoded at that 16q12.1 locus, a potential link between the PKC gene and these ABC transporters has been implicated.
To elucidate the physiological function of human ABCC11 and ABCC12, knockout mice are considered to be a useful animal model. For this reason, we have undertaken the present study to pursue mouse orthologues of ABCC11 and ABCC12. In this study, we have cloned the cDNA of mouse Abcc12 and characterized its chromosomal location, gene organization, tissue-specific expression, the putative protein structure, and splicing variants.
Section snippets
Cloning of mouse Abcc 12 cDNA
Mouse EST clones bearing a high similarity to partial sequences of human ABCC 12 cDNA were extracted from the NCBI mouse EST database and the mouse cDNA ‘FANTOM 2’ database of RIKEN (The FANTOM Consortium, 2002) by using the NCBI BLAST search program (Fig. 1). We have screened multiple tissue cDNA libraries (MTC, Clontech, Palo Alto, CA, USA) by PCR with the following primers deduced from the EST sequences: the forward primer, 5′-AGTTCCCTCATTTCAGCTCTCCTAGGAC-3′, and the backward primer,
Cloning and characterization of mouse Abcc 12 cDNA
Fig. 1 depicts the strategy of cloning mouse Abcc12 cDNA. The sequence of human ABCC12 cDNA was applied to the currently available mouse EST database on an NCBI BLAST search to discover ESTs encoding partial sequences of mouse Abcc 12. Thereby, the following EST clones were extracted: BB616859, BB615294, AI427812, AI614586, BE864084, AW060464, BB013432, BB014467, BB717705, and BB209897. In addition, in a search of the FANTOM 2 database of RIKEN, we found one cDNA clone (ID number=4932443H13)
Molecular characteristics of mouse Abcc12 cDNA
In the present study, we have cloned and characterized the cDNA of a new mouse ABC transporter, named Abcc12. The cloned cDNA was 4511 bp long and comprised a 4101 bp open reading frame. The deduced peptide consists of 1367 amino acid moieties, carrying two sets of Walker A, Walker B (Walker et al., 1982), and signature C (Higgins, 1992) motifs within the peptide (Fig. 2A). Based on the ATP binding cassettes and the putative trans-membrane spanning domains (Fig. 2B), Abcc12 is regarded as a
Acknowledgements
The authors thank Ms. Yukiko Saito (University of Tokyo Medical School) for her technical assistance in the preparation of tissue samples. This study was supported by research grants entitled ‘Studies on the genetic polymorphism and function of pharmacokinetics-related proteins in Japanese population’ (H12-Genome-026) and ‘Toxicoproteomics: expression of ABC transporter genes and drug–drug interactions’ (H14-Toxico-002) from the Japanese Ministry of Health and Welfare as well as by a
References (35)
- et al.
An oncological view on the blood-testis barrier
Lancet Oncol.
(2002) - et al.
High-efficiency full-length cDNA by biotinylated CAP trapper
Genomics
(1996) - et al.
Seven in absentia, a gene required for specification of R7 cell fate in the Drosophila eye
Cell
(1990) - et al.
Transport of cyclic nucleotides and estradiol 17-beta-d-glucuronide by multidrug resistance protein 4. Resistance to 6-mercaptopurine and 6-thioguanine
J. Biol. Chem.
(2001) - et al.
Chromosomal mapping of five conserved murine homologs of the Drosophila RING finger gene Seven-in-absentia
Genomics
(1997) - et al.
Characterization of human homologs of the Drosophila seven in absentia (sina) gene
Genomics
(1997) ATP/Mg2+-dependent cardiac transport system for glutathione S-conjugates: A study using rat heart sarcolemma vesicles
J. Biol. Chem.
(1989)The ATP-dependent glutathione S-conjugate export pump
Trends Biochem. Sci.
(1992)- et al.
The multidrug resistance protein 5 functions as an ATP-dependent export pump for cyclic nucleotides
J. Biol. Chem.
(2000) - et al.
An inventory of the human ABC proteins
Biochim. Biophys. Acta
(1999)
A simple method for displaying the hydropathic character of a protein
J. Mol. Biol.
The MRP encodes an ATP-dependent export pump of leukotriene C4 and structurally related conjugates
J. Biol. Chem.
pABC11 (also known as MOAT-C and MRP5), a member of the ABC family of proteins, has anion transporter activity but does not confer multidrug resistance when overexpressed in human embryonic kidney 293 cells
J. Biol. Chem.
Two new genes from the human ATP-binding cassette transporter superfamily, ABCC11 and ABCC12, tandemly duplicated on chromosome 16q12
Gene
Paroxysmal kinesigenic choreoathetosis locus maps to chromosome 16p11.2–p12.1
Am. J. Hum. Genet.
Multiple splicing variants of two new human ATP-binding cassette transporters, ABCC11 and ABCC12
Biochem. Biophys. Res. Commun.
ABCC13, an unusual truncated ABC transporter, is highly expressed in fetal human liver
Biochem. Biophys. Res. Commun.
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