ABCA5 resides in lysosomes, and ABCA5 knockout mice develop lysosomal disease-like symptoms.
ABCA5 is a member of the ABC transporter A subfamily, and a mouse orthologue (mABCA5) in newborn mouse brain and neural cells was identified by reverse transcription-PCR. Full-length cDNA cloning revealed that mABCA5 consists of 1,642 amino acid residues and that its putative structure is that of a full-type ABC transporter having two sets of six transmembrane segments and a nucleotide binding domain. Immunohistochemical studies revealed that mABCA5 is expressed in brain, lung, heart, and thyroid gland. A subcellular localization analysis showed that mABCA5 is a resident of lysosomes and late endosomes. Abca5(-)(/)(-) mice exhibited symptoms similar to those of several lysosomal diseases in heart, although no prominent abnormalities were found in brain or lung. They developed a dilated cardiomyopathy-like heart after reaching adulthood and died due to depression of the cardiovascular system. In addition, Abca5(-)(/)(-) mice also exhibited exophthalmos and collapse of the thyroid gland. Therefore, ABCA5 is a protein related to a lysosomal disease and plays important roles, especially in cardiomyocytes and follicular cells.
Pubmed ID: 15870284 RIS Download
ATP-Binding Cassette Transporters | Abnormalities, Multiple | Amino Acid Sequence | Animals | Cell Line | Cloning, Molecular | Exophthalmos | Female | Gene Deletion | Gene Expression Profiling | Humans | Immunohistochemistry | Lysosomes | Male | Mice | Mice, Knockout | Molecular Sequence Data | Myocardium | Protein Transport | RNA, Messenger | Rats | Reverse Transcriptase Polymerase Chain Reaction | Thyroid Gland | Thyroid Hormones