|
Plant Peptide Hormone
Peptide signaling plays a significant role in various aspects of plant growth and development and specific receptors for various peptides have been identified as being membrane-localized receptor kinases, the largest family of receptor-like molecules in plants. Signaling peptides include members of the following protein families. * Systemin — is a small polypeptide functioning as a long-distance signal to activate chemical defenses against herbivores. It was the first plant hormone proven to be a peptide. Systemin induces the production of protein defense compound called protease inhibitors. Systemin was first identified in tomato leaves. It was found to be an 18-amino acid peptide processed from the C-terminus of a 200-amino acid precursor, which is called prosystemin. * CLV3/ESR-related ('CLE') peptide family — ''CLV3'' encodes a small secreted peptide that functions as a short range ligand to the membrane-bound CLV1 receptor like kinase that together with CLV2 (a receptor- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Systemin
Systemin is a plant peptide hormone involved in the wound response in the family Solanaceae. It was the first plant hormone that was proven to be a peptide having been isolated from tomato leaves in 1991 by a group led by Clarence A. Ryan. Since then, other peptides with similar functions have been identified in tomato and outside of the Solanaceae. Hydroxyproline-rich glycoprotein, glycopeptides were found in Nicotiana, tobacco in 2001 and AtPeps (Arabidopsis thaliana plant elicitor peptide, Plant Elicitor Peptides) were found in ''Arabidopsis thaliana'' in 2006. Their precursors are found both in the cytoplasm and plant cell wall, cell walls of plant cells, upon insect damage, the precursors are processed to produce one or more mature peptides. The Receptor (biochemistry), receptor for systemin was first thought to be the same as the brassinolide receptor but this is now uncertain. The signal transduction processes that occur after the peptides bind are similar to the cytokin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peptide
Peptides (, ) are short chains of amino acids linked by peptide bonds. Long chains of amino acids are called proteins. Chains of fewer than twenty amino acids are called oligopeptides, and include dipeptides, tripeptides, and tetrapeptides. A polypeptide is a longer, continuous, unbranched peptide chain. Hence, peptides fall under the broad chemical classes of biological polymers and oligomers, alongside nucleic acids, oligosaccharides, polysaccharides, and others. A polypeptide that contains more than approximately 50 amino acids is known as a protein. Proteins consist of one or more polypeptides arranged in a biologically functional way, often bound to ligands such as coenzymes and cofactors, or to another protein or other macromolecule such as DNA or RNA, or to complex macromolecular assemblies. Amino acids that have been incorporated into peptides are termed residues. A water molecule is released during formation of each amide bond.. All peptides except cyclic pep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protease Inhibitor (biology)
In biology and biochemistry, protease inhibitors, or antiproteases, are molecules that inhibit the function of proteases (enzymes that aid the breakdown of proteins). Many naturally occurring protease inhibitors are proteins. In medicine, ''protease inhibitor'' is often used interchangeably with alpha 1-antitrypsin (A1AT, which is abbreviated PI for this reason). A1AT is indeed the protease inhibitor most often involved in disease, namely in alpha-1 antitrypsin deficiency. Classification Protease inhibitors may be classified either by the type of protease they inhibit, or by their mechanism of action. In 2004 Rawlings and colleagues introduced a classification of protease inhibitors based on similarities detectable at the level of amino acid sequence. This classification initially identified 48 families of inhibitors that could be grouped into 26 related superfamily (or clans) by their structure. According to the MEROPS database there are now 81 families of inhibitors. These fa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tomato
The tomato is the edible berry of the plant ''Solanum lycopersicum'', commonly known as the tomato plant. The species originated in western South America, Mexico, and Central America. The Mexican Nahuatl word gave rise to the Spanish word , from which the English word ''tomato'' derived. Its domestication and use as a cultivated food may have originated with the indigenous peoples of Mexico. The Aztecs used tomatoes in their cooking at the time of the Spanish conquest of the Aztec Empire, and after the Spanish encountered the tomato for the first time after their contact with the Aztecs, they brought the plant to Europe, in a widespread transfer of plants known as the Columbian exchange. From there, the tomato was introduced to other parts of the European-colonized world during the 16th century. Tomatoes are a significant source of umami flavor. They are consumed in diverse ways: raw or cooked, and in many dishes, sauces, salads, and drinks. While tomatoes are fruits ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ENOD40
''enod40'', also known as early nodulin 40, is a gene found in flowering plants. The gene has characteristics of both protein and Non-coding RNA genes. There is some evidence that the non-coding characteristics of this gene are more widely conserved than the protein coding sequences. In soyabeans ''enod40'' was found to be expressed during early stages of formation of nitrogen-fixing root nodules that are associated with symbiotic soil rhizobial bacteria. The gene is also active in roots containing fungi forming phosphate-acquiring arbuscular mycorrhiza. An interaction with a novel RNA-binding protein MtRBP1 (''Medicago truncatula'' RNA-binding protein 1) investigated in the development of Root nodule Root nodules are found on the roots of plants, primarily legumes, that form a symbiosis with nitrogen-fixing bacteria. Under nitrogen-limiting conditions, capable plants form a symbiotic relationship with a host-specific strain of bacteria known a ... suggests ENOD40 has a functi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phytosulfokine
Phytosulfokines are plant hormones that belong to the growing class of plant peptide hormones. Phytosulfokines are sulfated growth factor A growth factor is a naturally occurring substance capable of stimulating cell proliferation, wound healing, and occasionally cellular differentiation. Usually it is a secreted protein or a steroid hormone. Growth factors are important for regu ...s strongly promoting proliferation of plant cells in cultures. References * Plant peptide hormones {{botany-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
POLARIS (hormone)
Polaris is a star in the northern circumpolar constellation of Ursa Minor. It is designated α Ursae Minoris ( Latinized to ''Alpha Ursae Minoris'') and is commonly called the North Star or Pole Star. With an apparent magnitude that fluctuates around 1.98, it is the brightest star in the constellation and is readily visible to the naked eye at night. The position of the star lies less than 1° away from the north celestial pole, making it the current northern pole star. The stable position of the star in the Northern Sky makes it useful for navigation. As the closest Cepheid variable its distance is used as part of the cosmic distance ladder. The revised ''Hipparcos'' stellar parallax gives a distance to Polaris of about , while the successor mission ''Gaia'' gives a distance of about . Calculations by other methods vary widely. Although appearing to the naked eye as a single point of light, Polaris is a triple star system, composed of the primary, a yellow super ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rapid Alkalinization Factor
Rapids are sections of a river where the river bed has a relatively steep gradient, causing an increase in water velocity and turbulence. Rapids are hydrological features between a ''run'' (a smoothly flowing part of a stream) and a '' cascade''. Rapids are characterized by the river becoming shallower with some rocks exposed above the flow surface. As flowing water splashes over and around the rocks, air bubbles become mixed in with it and portions of the surface acquire a white color, forming what is called "whitewater". Rapids occur where the bed material is highly resistant to the erosive power of the stream in comparison with the bed downstream of the rapids. Very young streams flowing across solid rock may be rapids for much of their length. Rapids cause water aeration of the stream or river, resulting in better water quality. Rapids are categorized in classes, generally running from I to VI. A Class 5 rapid may be categorized as Class 5.1-5.9. While Class I rapids are e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sequence Homology
Sequence homology is the biological homology between DNA, RNA, or protein sequences, defined in terms of shared ancestry in the evolutionary history of life. Two segments of DNA can have shared ancestry because of three phenomena: either a speciation event (orthologs), or a duplication event (paralogs), or else a horizontal (or lateral) gene transfer event (xenologs). Homology among DNA, RNA, or proteins is typically inferred from their nucleotide or amino acid sequence similarity. Significant similarity is strong evidence that two sequences are related by evolutionary changes from a common ancestral sequence. Alignments of multiple sequences are used to indicate which regions of each sequence are homologous. Identity, similarity, and conservation The term "percent homology" is often used to mean "sequence similarity”, that is the percentage of identical residues (''percent identity''), or the percentage of residues conserved with similar physicochemical properties (' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
