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HNF1B
HNF1 homeobox B (hepatocyte nuclear factor 1 homeobox B), also known as HNF1B or transcription factor 2 (TCF2), is a human gene. Function HNF1B encodes hepatocyte nuclear factor 1-beta, a protein of the homeobox-containing basic helix-turn-helix family. The HNF1B protein is believed to form heterodimers with another member of this transcription factor family, HNF1A; depending on the HNF1B isoform, the result may be to activate or inhibit transcription of target genes. Deficiency of HNF1B cause abnormal maternal-Zygote transition and early embryogenesis failure. Mutation of HNF1B that disrupts normal function has been identified as the cause of MODY 5 ( Maturity-Onset of Diabetes, Type 5). A third human transcript variant is believed to exist based on such a variant in the rat: however, to date such an mRNA species has not been isolated. See also * Hepatocyte nuclear factors Hepatocyte nuclear factors (HNFs) are a group of phylogenetically unrelated transcription factors that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MODY 5
Renal cysts and diabetes syndrome (RCAD), also known as MODY 5 or HNF1B-MODY, is a form of maturity onset diabetes of the young. Presentation HNF1β-related MODY is one of the less common forms of MODY, with some distinctive clinical features, including atrophy of the pancreas and several forms of renal disease. HNF1β, also known as transcription factor 2 (TCF2), is involved in early stages of embryonic development of several organs, including the pancreas, where it contributes to differentiation of pancreatic endocrine Ngn3+ cell progenitors from non-endocrine embryonic duct cells. The gene is on chromosome 17q. The degree of insulin deficiency is variable. Diabetes can develop from infancy through middle adult life, and some family members who carry the gene remain free of diabetes into later adult life. Most of those who develop diabetes show atrophy of the entire pancreas, with mild or subclinical deficiency of exocrine as well as endocrine function. The non-pancreatic m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hepatocyte Nuclear Factors
Hepatocyte nuclear factors (HNFs) are a group of phylogenetically unrelated transcription factors that regulate the transcription of a diverse group of genes into proteins. These proteins include blood clotting factors and in addition, enzymes and transporters involved with glucose, cholesterol, and fatty acid transport and metabolism. Function As the name suggests, hepatocyte nuclear factors are expressed predominantly in the liver. However HNFs are also expressed and play important roles in a number of other tissues so that the name ''hepatocyte nuclear factor'' is somewhat misleading. Nevertheless, the liver is the only tissue in which a significant number of different HNFs are expressed at the same time. In addition, there are a number of genes which contain multiple promoter and enhancer regions each regulated by a different HNF. Furthermore, efficient expression of these genes require synergistic activation by multiple HNFs. Hence hepatocyte nuclear factors funct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homeobox
A homeobox is a Nucleic acid sequence, DNA sequence, around 180 base pairs long, that regulates large-scale anatomical features in the early stages of embryonic development. Mutations in a homeobox may change large-scale anatomical features of the full-grown organism. Homeoboxes are found within genes that are involved in the regulation of patterns of anatomical development (morphogenesis) in animals, fungus, fungi, plants, and numerous single cell eukaryotes. Homeobox genes encode homeodomain protein products that are transcription factors sharing a characteristic protein fold structure that binds DNA to regulate expression of target genes. Homeodomain proteins regulate gene expression and cell differentiation during early embryonic development, thus mutations in homeobox genes can cause developmental disorders. Homeosis is a term coined by William Bateson to describe the outright replacement of a discrete body part with another body part, e.g. antennapedia—replacement of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HNF1A
HNF1 homeobox A (hepatocyte nuclear factor 1 homeobox A), also known as HNF1A, is a human gene on chromosome 12. It is ubiquitously expressed in many tissues and cell types. The protein encoded by this gene is a transcription factor that is highly expressed in the liver and is involved in the regulation of the expression of several liver-specific genes. Mutations in the ''HNF1A'' gene have been known to cause diabetes. The ''HNF1A'' gene also contains a SNP associated with increased risk of coronary artery disease. Structure Gene The ''HNF1A'' gene resides on chromosome 12 at the band 12q24.2 and contains 10 exons. This gene produces 8 isoforms through alternative splicing. Protein This protein belongs to the HNF1 homeobox family. It contains 3 functional domains: an N-terminal dimerization domain ( residues 1–32), a bipartite DNA-binding motif containing an atypical POU-homeodomain (residues 98–280), and a C-terminal transactivation domain (residues 281–631). T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene
In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protein-coding genes and non-coding genes. During gene expression (the synthesis of Gene product, RNA or protein from a gene), DNA is first transcription (biology), copied into RNA. RNA can be non-coding RNA, directly functional or be the intermediate protein biosynthesis, template for the synthesis of a protein. The transmission of genes to an organism's offspring, is the basis of the inheritance of phenotypic traits from one generation to the next. These genes make up different DNA sequences, together called a genotype, that is specific to every given individual, within the gene pool of the population (biology), population of a given species. The genotype, along with environmental and developmental factors, ultimately determines the phenotype ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterodimer
In biochemistry, a protein dimer is a macromolecular complex or multimer formed by two protein monomers, or single proteins, which are usually non-covalently bound. Many macromolecules, such as proteins or nucleic acids, form dimers. The word ''dimer'' has roots meaning "two parts", '' di-'' + '' -mer''. A protein dimer is a type of protein quaternary structure. A protein homodimer is formed by two identical proteins while a protein heterodimer is formed by two different proteins. Most protein dimers in biochemistry are not connected by covalent bonds. An example of a non-covalent heterodimer is the enzyme reverse transcriptase, which is composed of two different amino acid chains. An exception is dimers that are linked by disulfide bridges such as the homodimeric protein NEMO. Some proteins contain specialized domains to ensure dimerization (dimerization domains) and specificity. The G protein-coupled cannabinoid receptors have the ability to form both homo- and hetero ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Embryogenesis
An embryo ( ) is the initial stage of development for a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male sperm cell. The resulting fusion of these two cells produces a single-celled zygote that undergoes many cell divisions that produce cells known as blastomeres. The blastomeres (4-cell stage) are arranged as a solid ball that when reaching a certain size, called a morula, (16-cell stage) takes in fluid to create a cavity called a blastocoel. The structure is then termed a blastula, or a blastocyst in mammals. The mammalian blastocyst hatches before implantating into the endometrial lining of the womb. Once implanted the embryo will continue its development through the next stages of gastrulation, neurulation, and organogenesis. Gastrulation is the formation of the three germ layers that will form all of the different parts o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
