| ATS | Achard-Thiers syndrome; acid test solution; alpha-D-tocopherol acid succinate; American Thoracic Soc... |
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| ADP | adenopathy; adenosine diphosphate; administrative psychiatry; approved drug product; area diastolic ... |
| BDIP | biomedical digital image processing |
| CPU | caudate putamen; central processing unit |
| DP | data processing; deep pulse; definitive procedure; degradation product; degree of polymerization; de... |
| signal recognition particle | A complex between a 7S RNA and six proteins. SRP binds to the nascent polypeptide chain of eukaryotic proteins with a signal sequence and halts further translation until the ribosome becomes associated with the rough endoplasmic reticulum. One of the SRP proteins (srp54) binds GTP and in association with 7SRNA and srp19 has GTPase activity. (18 Nov 1997) |
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| signal recognition particle receptor | Receptor for the signal recognition particle (SRP) found in the membrane of the endoplasmic reticulum. Also called docking protein. Heterodimeric, both protomers having GTP binding capacity, though dissimilar binding sites. Not until the complex of SRP, ribosome, message and nascent polypeptide chain binds to the SRP receptor is the block to further chain elongation released and concurrently the SRP is released, leaving the ribosome attached to the endoplasmic reticulum membrane. Cotranslational transport of the polypeptide delivers it into the lumen of the ER. (18 Nov 1997) |
| signal response coupling | The cascade of processes by which an extracellular signal (typically a hormone or neurotransmitter) interacts with a receptor at the cell surface, causing a change in the level of a second messenger for example calcium or cyclic AMP) and ultimately effects a change in the cells functioning (for example: triggering glucose uptake or initiating cell division). Can also be applied to sensory signal transduction, for example of light at photoreceptors. (18 Nov 1997) |
| signal sequence | A peptide present on proteins that are destined either to be secreted or to be membrane components. It is usually at the N terminus and normally absent from the mature protein. Normally refers to the sequence (ca 20 amino acids) that interacts with signal recognition particle and directs the ribosome to the endoplasmic reticulum where co translational insertion takes place. Could also refer to sequences that direct post translational uptake by organelles. Signal peptides are highly hydrophobic but with some positively charged residues. The signal sequence is normally removed from the growing peptide chain by signal peptidase, a specific protease located on the cisternal face of the endoplasmic reticulum. See: signal recognition particle. (18 Nov 1997) |
| signal-to-noise ratio | <microscopy> Also sometimes used as an abbreviation for serial number, can be somewhat confusing in the case of electronic equipment. (05 Aug 1998) |
| signal transduction | The cascade of processes by which an extracellular signal (typically a hormone or neurotransmitter) interacts with a receptor at the cell surface, causing a change in the level of a second messenger for example calcium or cyclic AMP) and ultimately effects a change in the cells functioning (for example: triggering glucose uptake or initiating cell division). Can also be applied to sensory signal transduction, for example of light at photoreceptors. (18 Nov 1997) |
| signal void | In magnetic resonance imaging, a region emitting no radiofrequency signal, either because there are no activated protons in the region (such as flowing blood) or because a different element predominates, particularly calcium. (05 Mar 2000) |
| nuclear localization signal | Short, predominantly basic amino acid sequences identified as nuclear import signals for some proteins. These sequences are believed to interact with specific receptors at nuclear pores. (12 Dec 1998) |
| antigen processing | Modification of an antigen by accessory cells. This usually involves endocytosis of the antigen and either minimal cleavage or unfolding. The processed antigen is then presented in modified form by the accessory cell. (18 Nov 1997) |
| automatic data processing | Data processing largely performed by automatic means. (12 Dec 1998) |
| batch processing | <technique> Growth in a closed system with a specific amount of nutrient medium. In bioprocessing, defined amounts of nutrient material and living matter are placed in a bioreactor and removed when the process is completed. (14 Nov 1997) |
| calcium-independent processing protease | <enzyme> Converts hiv-1 gp160 precursor to gp120 and gp41 Registry number: EC 3.4.- Synonym: viral envelope glycoprotein maturase, vem enzyme (26 Jun 1999) |
| matrix processing peptidase | <enzyme> From matrix fraction of rat liver mitochondria; cleaves mitochondrial protein precursors; inhibited by metal chelators and reactived by mn2+; classified as EC 3.4.24.64 Registry number: EC 3.4.24.- Synonym: mitochondrial processing peptidase, mitochondrial processing protease, alpha-mpp, beta-mpp, p-52 protein, rat, p-55 protein, rat, mas1 protein, yeast, mas2 protein, yeast (26 Jun 1999) |
| gp160 processing protease | <enzyme> Converts hiv gp160 to gp120 and gp41, cleaving between arg511 and ala512 Registry number: EC 3.4.99.- (26 Jun 1999) |
| RNA processing | <molecular biology> Modifications of primary RNA trancripts including splicing, cleavage, base modification, capping and the addition of poly A tails. See: RNA editing. (23 Aug 1998) |