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RNU4ATAC
RNA, U4atac small nuclear (U12-dependent splicing) is a small nuclear RNA that in humans is encoded by the ''RNU4ATAC'' gene. The small nuclear RNA (snRNA) encoded by this gene is part of the U12-dependent minor spliceosome complex. In addition to the encoded RNA, this ribonucleoprotein complex consists of U11, U12, U5, and U6atac snRNAs. The U12-dependent spliceosome is required for the splicing of approximately 700 specific introns in the human genome. Genomics The ''RNU4ATAC'' gene is located on chromosome 2 (2q14.2). It is a single copy gene that is embedded within an intron of the protein coding ''CLASP1'' gene but is transcribed in the antisense direction from ''CLASP1''. Clinical importance Defects in this gene are a cause of several human inherited syndromes all of which show autosomal recessive inheritance. These include Taybi Linder syndrome (microcephalic osteodysplastic primordial dwarfism type 1 (MOPD1), Roifman syndrome and Lowry-Wood syndrome Lowry-Wood sy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromosome 2
Chromosome 2 is one of the twenty-three pairs of chromosomes in humans. People normally have two copies of this chromosome. Chromosome 2 is the second-largest human chromosome, spanning more than 242 million base pairs and representing almost eight percent of the total DNA in human cells. Chromosome 2 contains the HOXD homeobox gene cluster. Chromosomes Humans have only twenty-three pairs of chromosomes, while all other extant members of Hominidae have twenty-four pairs. It is believed that Neanderthals and Denisovans had twenty-three pairs. Human chromosome 2 is a result of an end-to-end fusion of two ancestral chromosomes.It has been hypothesized that Human Chromosome 2 is a fusion of two ancestral chromosomes by Alec MacAndrew; accessed 18 May 2006.< ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Primordial Dwarfism
Primordial dwarfism (PD) is a form of dwarfism that results in a smaller body size in all stages of life beginning from before birth. More specifically, primordial dwarfism is a diagnostic category including specific types of profoundly proportionate dwarfism, in which individuals are extremely small for their age, even as a fetus. Most individuals with primordial dwarfism are not diagnosed until they are about 3–5 years of age. Medical professionals typically diagnose the fetus as being small for gestational age, or as showing intrauterine growth restriction when an ultrasound is conducted. Typically, people with primordial dwarfism are born with very low birth weights. After birth, growth continues at a much slower rate, leaving individuals with primordial dwarfism perpetually years behind their peers in stature and in weight. Most cases of short stature are caused by skeletal or endocrine disorders. The five subtypes of primordial dwarfism are among the most severe forms of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Small Nuclear RNA
Small nuclear RNA (snRNA) is a class of small RNA molecules that are found within the splicing speckles and Cajal bodies of the cell nucleus in eukaryotic cells. The length of an average snRNA is approximately 150 nucleotides. They are transcribed by either RNA polymerase II or RNA polymerase III. Their primary function is in the processing of pre-messenger RNA (hnRNA) in the nucleus. They have also been shown to aid in the regulation of transcription factors (7SK RNA) or RNA polymerase II (B2 RNA), and maintaining the telomeres. snRNA are always associated with a set of specific proteins, and the complexes are referred to as small nuclear ribonucleoproteins (snRNP, often pronounced "snurps"). Each snRNP particle is composed of a snRNA component and several snRNP-specific proteins (including Sm proteins, a family of nuclear proteins). The most common human snRNA components of these complexes are known, respectively, as: U1 spliceosomal RNA, U2 spliceosomal RNA, U4 spliceosomal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene
In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a basic unit of heredity and 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 noncoding genes. During gene expression, the DNA is first copied into RNA. The RNA can be directly functional or be the intermediate template for a protein that performs a function. The transmission of genes to an organism's offspring is the basis of the inheritance of phenotypic traits. These genes make up different DNA sequences called genotypes. Genotypes along with environmental and developmental factors determine what the phenotypes will be. Most biological traits are under the influence of polygenes (many different genes) as well as gen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spliceosome
A spliceosome is a large ribonucleoprotein (RNP) complex found primarily within the nucleus of eukaryotic cells. The spliceosome is assembled from small nuclear RNAs (snRNA) and numerous proteins. Small nuclear RNA (snRNA) molecules bind to specific proteins to form a small nuclear ribonucleoprotein complex (snRNP, pronounced “snurps”), which in turn combines with other snRNPs to form a large ribonucleoprotein complex called a spliceosome. The spliceosome removes introns from a transcribed pre-mRNA, a type of primary transcript. This process is generally referred to as splicing. An analogy is a film editor, who selectively cuts out irrelevant or incorrect material (equivalent to the introns) from the initial film and sends the cleaned-up version to the director for the final cut. However, sometimes the RNA within the intron acts as a ribozyme, splicing itself without the use of a spliceosome or protein enzymes. History In 1977, work by the Sharp and Roberts labs reveale ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
