Characterization of the Bex gene family in humans, mice, and rats
| Autor: | Enrique Alvarez, Curt R. Freed, Samir E. Witta, Wenbo Zhou |
|---|---|
| Rok vydání: | 2005 |
| Předmět: |
Cytoplasm
Proteasome Endopeptidase Complex Dopamine Molecular Sequence Data Nerve Tissue Proteins Biology Mice Chromosome 16 Species Specificity Sequence Homology Nucleic Acid Gene expression Genetics Animals Humans Gene family Muscle Skeletal Gene X chromosome Oligonucleotide Array Sequence Analysis Cell Nucleus Neurons Chromosomes Human X Base Sequence Oligonucleotide Gene Expression Profiling Brain Gene Expression Regulation Developmental Heart Haplorhini General Medicine Subcellular localization Molecular biology Rats Liver Spinal Cord Organ Specificity Suppression subtractive hybridization Multigene Family |
| Zdroj: | Gene. 357:18-28 |
| ISSN: | 0378-1119 |
| DOI: | 10.1016/j.gene.2005.05.012 |
| Popis: | To better understand the development of ventral mesencephalic dopamine neurons, we performed subtractive hybridization screens to find ventral mesencephalic genes expressed at rat embryonic day 10 when these neurons begin to differentiate. The most commonly identified genes in these screens were members of the Bex (Brain expressed X-linked) gene family, rat Bex1 (Rex3), and a novel gene, rat Bex4. After identifying these genes, we then sought to characterize the Bex gene family. Two additional novel Bex genes (human Bex5 and mouse Bex6) were discovered through genomic databases. Bex5 is present in humans and monkeys, but not rodents, while Bex6 exists in mice, but not humans. Bex4 and Bex5 are localized to the X chromosome, are expressed in brain, and are similar in sequence. Bex4 and Bex5 are 54% and 56% identical to human Bex3 (pHGR74, NADE). Mouse Bex6 is on chromosome 16 and is 67% identical to mouse Bex4. Human Bex gene expression was studied with tissue expression arrays probed with specific oligonucleotides. Human Bex1 and Bex2 have similar expression patterns in the central nervous system with high levels in pituitary, cerebellum, and temporal lobe, and Bex1 is widely expressed outside of the central nervous system with high expression in the liver. Human Bex4 is highly expressed in heart, skeletal muscle, and liver, while Bex3 and Bex5 are more widely expressed. The subcellular localization of the Bex proteins varies from nuclear (rat Bex1) to cytoplasmic (rat Bex3, human Bex5, and mouse Bex6) and to both nuclear and cytoplasmic (rat Bex2 and rat Bex4). Rat Bex3, rat Bex4, human Bex5, and mouse Bex6 are degraded by the proteasome, while rat Bex1 or Bex2 are not. Rat Bex3 protein can likely bind transition metals through a histidine-rich domain. Because this gene family was originally named Bex and because these genes are unified by sequence similarity and gene structure, we believe the Bex nomenclature should prevail over nomenclature based on function (NADE) that has not been extended to the other Bex genes. We conclude that the Bex gene family members are highly homologous but differ in their expression patterns, subcellular localization, and degradation by the proteasome. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect