Alternative titles; symbolsBICAUDAL D, DROSOPHILA, HOMOLOG OF, 1HGNC Approved Gene Symbol: BICD1Cytogenetic location: 12p11.21 Genomic coordinates (GRCh38): ...
Alternative titles; symbols
HGNC Approved Gene Symbol: BICD1
Cytogenetic location: 12p11.21 Genomic coordinates (GRCh38): 12:32,106,772-32,383,636 (from NCBI)
▼ Cloning and Expression
From the early part of the 20th century, embryologists recognized that the cytoplasmic asymmetry established in the egg during oogenesis directs the proper spatial development of the embryo. Development of this polarity in the Drosophila oocyte depends also on the correct sorting of maternal RNAs. Bicaudal D is a Drosophila protein that is involved in establishing the asymmetric cytoplasm in the developing oocyte. The gene encodes a cytoskeleton-like coiled-coil polypeptide, with a leucine zipper and 5 alpha-helix domains or heptad repeats showing sequence similarity to the tail domains of myosin heavy chains (e.g., 160730), the microtubule motor kinesin (see 600025), and intermediate filament proteins. Using a hybridization selection procedure with cosmids derived from chromosome 12p, Baens et al. (1995) isolated a cDNA fragment homologous to bicaudal D. Using a PCR-mediated cDNA cloning strategy, Baens and Marynen (1997) obtained the coding sequence of the human homolog (BICD1) and generated a partial mouse Bicd1 cDNA. They found that predicted amino acid sequence similarity of the BICD1 cDNA was limited essentially to the amphipatic helices and the leucine zipper, but the conserved order of these domains suggested a function of the protein in mammals similar to that in Drosophila. A database search further indicated the existence of a second human homolog on 9q and a Caenorhabditis elegans homolog. Northern blot analysis indicated that both the human and the murine homologs produce an mRNA species of approximately 9.5 kb expressed in brain, heart, and skeletal muscle, as well as during mouse embryonic development. The conserved structural characteristics of BICD1 protein and its expression in muscle and especially brain suggested to Baens and Marynen (1997) that BICD1 is a component of a cytoskeleton-based mRNA sorting mechanism conserved during evolution.
▼ Gene Function
Bullock and Ish-Horowicz (2001) demonstrated in Drosophila that the same machinery and RNA signals drive specific accumulation of maternal RNAs in the early oocyte and apical transcript localization in blastoderm embryos. They demonstrated in vivo that Egalitarian (Egl) and bicaudal D (BicD), maternal proteins required for oocyte determination, are selectively recruited by, and cotransported with, localizing transcripts in blastoderm embryos, and that interfering with the activities of Egl and BicD blocks apical localization.
▼ Molecular Genetics
For discussion of a possible association between variation in the BICD1 gene and leukocyte telomere length, see 609113.