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HNRNPC
Heterogeneous nuclear ribonucleoproteins C1/C2 is a protein that in humans is encoded by the ''HNRNPC'' gene. It is abnormally expressed in fetuses of both IVF and ICSI, which may contribute to the increase risk of birth defects in these ART. Function This gene belongs to the subfamily of ubiquitously expressed heterogeneous nuclear ribonucleoproteins (hnRNPs). The hnRNPs are RNA binding proteins and they complex with heterogeneous nuclear RNA (hnRNA). These proteins are associated with pre-mRNAs in the nucleus and appear to influence pre-mRNA processing(reference: Koenig J. nature structural and Molecular Biology 2010: iCLIP) and other aspects of mRNA metabolism and transport. While all of the hnRNPs are present in the nucleus, some seem to shuttle between the nucleus and the cytoplasm. The hnRNP proteins have distinct nucleic acid binding properties. Transcriptional regulation by hormonal 1,25-dihydroxyvitamin D(3) (calcitriol) involves occupancy of vitamin D response elemen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterogeneous Nuclear Ribonucleoprotein
Heterogeneous nuclear ribonucleoproteins (hnRNPs) are complexes of RNA and protein present in the cell nucleus during transcription (genetics), gene transcription and subsequent post-transcriptional modification of the newly synthesized RNA (pre-mRNA). The presence of the proteins bound to a pre-mRNA molecule serves as a signal that the pre-mRNA is not yet fully processed and therefore not ready for export to the cytoplasm. Since most mature RNA is exported from the nucleus relatively quickly, most RNA-binding protein in the nucleus exist as heterogeneous ribonucleoprotein particles. After splicing has occurred, the proteins remain bound to spliced introns and target them for degradation. hnRNPs are also integral to the Eukaryotic small ribosomal subunit (40S), 40S subunit of the ribosome and therefore important for the translation of mRNA in the cytoplasm. However, hnRNPs also have their own nuclear localization sequences (NLS) and are therefore found mainly in the nucleus. Though ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metabolic reactions, DNA replication, Cell signaling, responding to stimuli, providing Cytoskeleton, structure to cells and Fibrous protein, organisms, and Intracellular transport, transporting molecules from one location to another. Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the Nucleic acid sequence, nucleotide sequence of their genes, and which usually results in protein folding into a specific Protein structure, 3D structure that determines its activity. A linear chain of amino acid residues is called a polypeptide. A protein contains at least one long polypeptide. Short polypeptides, containing less than 20–30 residues, are rarely considered to be proteins and are commonly called pep ... [...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] |
In Vitro Fertilization
In vitro fertilisation (IVF) is a process of fertilisation in which an egg is combined with sperm in vitro ("in glass"). The process involves monitoring and stimulating the ovulatory process, then removing an ovum or ova (egg or eggs) from the ovaries and enabling sperm to fertilise them in a culture medium in a laboratory. After a fertilised egg (zygote) undergoes embryo culture for 2–6 days, it is transferred by catheter into the uterus, with the intention of establishing a successful pregnancy. IVF is a type of assisted reproductive technology used to treat infertility, enable gestational surrogacy, and, in combination with pre-implantation genetic testing, avoid the transmission of abnormal genetic conditions. When a fertilised egg from egg and sperm donors implants in the uterus of a genetically unrelated surrogate, the resulting child is also genetically unrelated to the surrogate. Some countries have banned or otherwise regulated the availability of IVF treatme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intracytoplasmic Sperm Injection
Intracytoplasmic sperm injection (ICSI ) is an in vitro fertilization (IVF) procedure in which a single sperm cell is injected directly into the cytoplasm of an egg. This technique is used in order to prepare the gametes for the obtention of embryos that may be transferred to a maternal uterus. With this method, the acrosome reaction is skipped. There are several differences between classic IVF and ICSI. However, the steps to be followed before and after insemination are the same. In terms of insemination, ICSI needs only one sperm cell per oocyte, while IVF needs 50,000–100,000. This is because the acrosome reaction has to take place and thousands of sperm cells have to be involved in IVF. Once fertilized, the egg is transformed into a pre-embryo and it has to be transferred to the uterus to continue its development. The first human pregnancy generated by ICSI was carried out in 1991 by Gianpiero Palermo and his team. Round spermatid injection (ROSI) Round spermatid injecti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Assisted Reproductive Technology
Assisted reproductive technology (ART) includes medical procedures used primarily to address infertility. This subject involves procedures such as in vitro fertilization (IVF), intracytoplasmic sperm injection (ICSI), and cryopreservation of gametes and embryos, and the use of fertility medication. When used to address infertility, ART may also be referred to as fertility treatment. ART mainly belongs to the field of reproductive endocrinology and infertility. Some forms of ART may be used with regard to fertile couples for genetic purpose (see preimplantation genetic diagnosis). ART may also be used in surrogacy arrangements, although not all surrogacy arrangements involve ART. The existence of sterility will not always require ART to be the first option to consider, as there are occasions when its cause is a mild disorder that can be solved with more conventional treatments or with behaviors based on promoting health and reproductive habits. Procedures General With ART, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcitriol
Calcitriol is a hormone and the active form of vitamin D, normally made in the kidney. It is also known as 1,25-dihydroxycholecalciferol. It binds to and activates the vitamin D receptor in the nucleus of the cell, which then increases the expression of many genes. Calcitriol increases blood Calcium in biology, calcium mainly by increasing the uptake of calcium from the intestines. It can be given as a medication for the treatment of hypocalcemia, low blood calcium and hyperparathyroidism due to kidney disease, low blood calcium due to hypoparathyroidism, osteoporosis, osteomalacia, and familial hypophosphatemia, and can be taken by mouth or by intravenous, injection into a vein. Excessive amounts or intake can result in weakness, headache, nausea, constipation, urinary tract infections, and abdominal pain. Serious side effects may include high blood calcium and anaphylaxis. Calcitriol was identified as the active form of vitamin D in 1971 and the drug was approved for medic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
VDRE
Vitamin D response element (VDRE) is a type of DNA sequence that is found in the promoter region of vitamin D regulated genes. This sequence binds the vitamin D receptor (VDR), when complexed with calcitriol (1,25(OH)2D), the active form of vitamin D, and so regulates the expression of many genes. These response elements typically consist of two conserved hexameric half-sites separated by a three nucleotide spacer, referred to as a DR3 (for direct repeat spaced by 3 type element). The sequence of a VDRE can have a strong influence on the degree of protein binding, particularly at the fifth position in the half-site, and many studies have focused on synthetic variations of response elements and not naturally occurring sequences. The VDR is widely distributed in tissues, and is not restricted to those tissues considered the classic targets of vitamin D. The VDR upon binding to 1,25(OH)2D heterodimerizes with other nuclear hormone receptors, in particular the family of retinoid X recep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcitriol Receptor
The vitamin D receptor (VDR also known as the calcitriol receptor) is a member of the nuclear receptor family of transcription factors. Calcitriol (the active form of vitamin D, 1,25-(OH)2vitamin D3) binds to VDR, which then forms a heterodimer with the retinoid-X receptor. The VDR heterodimer then enters the nucleus and binds to Vitamin D responsive elements (VDRE) in genomic DNA. VDR binding results in expression or transrepression of many specific gene products. VDR is also involved in microRNA-directed post transcriptional mechanisms. In humans, the vitamin D receptor is encoded by the ''VDR'' gene located on chromosome 12q13.11. VDR is expressed in most tissues of the body, and regulates transcription of genes involved in intestinal and renal transport of calcium and other minerals. Glucocorticoids decrease VDR expression. Many types of immune cells also express VDR. Function The VDR gene encodes the nuclear hormone receptor for vitamin D. The most potent natural ag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
