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AKAP3
A-kinase anchor protein 3 is an enzyme that in humans is encoded by the ''AKAP3'' gene. Function The A-kinase anchor proteins (AKAPs) are a group of structurally diverse proteins, which have the common function of binding to the regulatory subunit of protein kinase A (PKA) and confining the holoenzyme to discrete locations within the cell. This gene encodes a member of the AKAP family, and is expressed in testis only. The encoded protein contains an RII-binding domain, and is predicted to participate in protein-protein interactions with the R-subunit of the PKA. This protein is localized to the ribs of the fibrous sheath in the principal piece of the sperm tail. It may function as a regulator of both motility- and head-associated functions such as capacitation and the acrosome reaction. Interactions AKAP3 has been shown to interact with: * AKAP4 * GNA13 Guanine nucleotide-binding protein subunit alpha-13 is a protein that in humans is encoded by the ''GNA13'' gene. Inter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AKAP4
A-kinase anchor protein 4 is a scaffold protein that in humans is encoded by the ''AKAP4'' gene. It involves in the intracellular signalling of protein kinase -A. AKAP4 is called as cancer /testis antigen (CTA), it belongs to a class of tumour linked antigens categories by high expression in germ cells and cancer than normal tissues. AKAP4 is not normally expressed in mRNA and protein level in MM cell line. Function The A-kinase anchor proteins (AKAPs) are a group of structurally diverse proteins, which have the common function of binding to the regulatory subunit of protein kinase A (PKA) and confining the holoenzyme to discrete locations within the cell. This gene encodes a member of the AKAP family. The encoded protein is localized to the sperm flagellum and may be involved in the regulation of sperm motility. Alternative splicing of this gene results in two transcript variants encoding different isoforms. AKAP 4 protein belongs to the family of scaffold proteins and is invo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GNA13
Guanine nucleotide-binding protein subunit alpha-13 is a protein that in humans is encoded by the ''GNA13'' gene. Interactions and functions The GNA13 gene encodes the G13 G protein alpha subunit. Together with GNA12, these two proteins comprise one of the four classes of heterotrimeric G protein alpha subunits. Heterotrimeric G proteins function in transducing hormone and neurotransmitter signals detected by cell surface G protein-coupled receptors to intracellular signaling pathways to modulate cell functions. G protein alpha subunits bind to guanine nucleotides and function in a regulatory cycle, and are active when bound to GTP but inactive and associated with the G beta-gamma complex when bound to GDP. Active GTP-bound G12 alpha subunit interacts with and activates ARHGEF1, ARHGEF11, and ARHGEF12. These ARHGEF proteins function as guanine nucleotide exchange factors for the Rho small GTPases to regulate the actin cytoskeleton. GNA13 has been shown to interact w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PRKAR2A
cAMP-dependent protein kinase type II-alpha regulatory subunit is an enzyme that in humans is encoded by the ''PRKAR2A'' gene. Function cAMP is a signaling molecule important for a variety of cellular functions. cAMP exerts its effects by activating the cAMP-dependent Protein Kinase, more commonly called Protein Kinase A (PKA), which transduces the signal through phosphorylation of different target proteins. The inactive holoenzyme of PKA is a tetramer composed of two regulatory and two catalytic subunits. cAMP causes the dissociation of the inactive holoenzyme into a dimer of regulatory subunits bound to four cAMP and two free monomeric catalytic subunits. Four different regulatory subunits and three catalytic subunits of PKA have been identified in humans. The protein encoded by this gene is one of the regulatory subunits. This subunit can be phosphorylated by the activated catalytic subunit. It may interact with various A-kinase anchoring proteins ( AKAPs) and determine the su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. Almost all metabolic processes in the cell need enzyme catalysis in order to occur at rates fast enough to sustain life. Metabolic pathways depend upon enzymes to catalyze individual steps. The study of enzymes is called ''enzymology'' and the field of pseudoenzyme analysis recognizes that during evolution, some enzymes have lost the ability to carry out biological catalysis, which is often reflected in their amino acid sequences and unusual 'pseudocatalytic' properties. Enzymes are known to catalyze more than 5,000 biochemical reaction types. Other biocatalysts are catalytic RNA molecules, called ribozymes. Enzymes' specificity comes from their unique three-dimensional structures. Like all catalysts, enzymes increase the react ... [...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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein Kinase A
In cell biology, protein kinase A (PKA) is a family of enzymes whose activity is dependent on cellular levels of cyclic AMP (cAMP). PKA is also known as cAMP-dependent protein kinase (). PKA has several functions in the cell, including regulation of glycogen, sugar, and lipid metabolism. It should not be confused with 5'-AMP-activated protein kinase ( AMP-activated protein kinase). History Protein kinase A, more precisely known as adenosine 3',5'-monophosphate (cyclic AMP)-dependent protein kinase, abbreviated to PKA, was discovered by chemists Edmond H. Fischer and Edwin G. Krebs in 1968. They won the Nobel Prize in Physiology or Medicine in 1992 for their work on phosphorylation and dephosphorylation and how it relates to PKA activity. PKA is one of the most widely researched protein kinases, in part because of its uniqueness; out of 540 different protein kinase genes that make up the human kinome, only one other protein kinase, casein kinase 2, is known to exist in a phy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acrosome
The acrosome is an organelle that develops over the anterior (front) half of the head in the spermatozoa (sperm cells) of many animals including humans. It is a cap-like structure derived from the Golgi apparatus. In placental mammals the acrosome contains degradative enzymes (including hyaluronidase and acrosin). These enzymes break down the outer membrane of the ovum, called the zona pellucida, allowing the haploid nucleus in the sperm cell to join with the haploid nucleus in the ovum. This shedding of the acrosome, or acrosome reaction, can be stimulated '' in vitro'' by substances a sperm cell may encounter naturally such as progesterone or follicular fluid, as well as the more commonly used calcium ionophore A23187. This can be done to serve as a positive control when assessing the acrosome reaction of a sperm sample by flow cytometry or fluorescence microscopy. This is usually done after staining with a fluoresceinated lectin such as FITC-PNA, FITC-PSA, FITC-ConA, or fl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
