1,440 articles
Spectral flow cytometry
Spectral flow cytometry is a single-cell analysis technique that measures the full fluorescence spectrum of each cell, separating dyes by spectral unmixing in panels of up to 50 colors.
Spheroplast
Spheroplasts: bacteria or yeast that have partially lost their cell wall and become round; wall-less Gram-negative forms retaining an outer membrane, used in patch clamp, imaging, transformation, and DNA delivery.
SPI-1 type 3 secretion system stator protein
OrgB (SctL), the SPI-1 T3SS stator protein of Salmonella, homolog of flagellar FliH; ATPase regulator forming spoke-like dimers linking SpaO sorting-platform pods to the InvC ATPase.
Spindle apparatus
Spindle apparatus (mitotic spindle): microtubule structure of cell division with two spindle poles and astral, polar, and kinetochore microtubules; segregates chromosomes, targeted by taxanes and vinca alkaloids.
Spindle orientation and cleavage-plane specification
Spindle orientation and cleavage-plane specification: how dividing cells position the mitotic spindle via astral microtubules, cortical dynein, and the conserved Gαi–LGN–NuMA complex to set the cleavage plane, daughter-cell size, and fate.
Spinning disk confocal microscopy
Spinning disk confocal microscopy (SDCM) is a fluorescence technique that forms optical sections through a rotating disk of pinholes, enabling fast, low-phototoxicity 3D imaging of living cells.
Spinous cell
Spinous cells (prickle cells) are keratinocytes of the stratum spinosum, the epidermal layer above the basal layer; named for desmosomal spines, they express K1/K10 and become granular cells.
Sq-1
Sq-1 (CVCL_4900, RRID:CVCL_4900) is a human lung squamous cell carcinoma cancer cell line from a Japanese male, carrying EGFR L858R (in 10% of cells) and a TP53 splice donor mutation, distributed as RCB1905 and TKG 0301.
SsrA-binding protein
SsrA-binding protein (SmpB, small protein B) is the bacterial tmRNA-binding protein essential for trans-translation, rescuing stalled ribosomes; OB-fold β-barrel with C-terminal tail, present in 97% of bacterial genomes, proposed antimicrobial drug target.
ST88-14
ST88-14 (CVCL_8916) is a human NF1-associated malignant peripheral nerve sheath tumor cell line from a 24-year-old man's retroperitoneal tumor, neurofibromin-deficient, and the genuine line behind the misidentified T265.
Start codon
A start codon, or initiation codon, is the codon, usually AUG, that begins a gene's coding region and directs protein translation by binding the initiator tRNA.
Staygreen protein
Staygreen protein (SGR, NYE1), a conserved chloroplast Mg-dechelatase that initiates chlorophyll degradation during leaf senescence; sgr mutants stay green, including Mendel's pea.
STED nanoscopy
STED nanoscopy is a super-resolution fluorescence microscopy method that switches off fluorophores around the focus with a donut-shaped laser beam, reaching resolutions of tens of nanometers.
Stem cell
A stem cell is a cell that can both replicate itself and differentiate into specialized cell types; types include embryonic, adult, and laboratory-made induced pluripotent stem cells.
Stem cell isolation
Stem cell isolation is the set of laboratory methods for separating rare stem cells from mixed populations in tissues, blood, or cultures, producing enriched cells for transplantation and research.
Stem cell of epidermis
Epidermal stem cells (EPSCs, skin epithelial stem cells) are self-renewing adult stem cells in the epidermis and hair follicle bulge that generate keratinocytes, hairs, and sebocytes, and underpin cultured epidermal autograft, vitiligo, and gene-corrected epidermolysis bullosa therapies.
Stem cells
Stem Cells (STEM CELLS) is a monthly peer-reviewed journal on stem cell biology, founded 1981 by Metcalf, Lajtha, and Takaku, published by AlphaMed Press then Oxford University Press since 2022, ISSN 1066-5099.
Steroidogenic acute regulatory protein
StAR (STARD1) is a mitochondrial protein that transports cholesterol across mitochondrial membranes for pregnenolone synthesis, the rate-limiting step of steroidogenesis; mutations cause congenital lipoid adrenal hyperplasia.
Steven P. Gross
Steven P. Gross is an American biophysicist and professor of developmental and cell biology at UC Irvine who studies how cells move cargo along microtubules with molecular motors such as kinesin and dynein.
Stiftchenzellen
Stiftchenzellen are sensory epidermal cells of frog tadpoles described by Kölliker in 1885 and identified by electron microscopy by Whitear in 1976; they bear apical microvilli, form synaptic contacts with epidermal nerve fibres, and are proposed chemoreceptors.
Storage cell
Storage cell (Cell Ontology CL:0000629): a cell specialized to store substances later released for a purpose; child of stuff accumulating cell. Also names for a one-object AFS computing location, an accelerator gas-target cell, and an oil compartment in gravity base structures.
Stretch-activated cation channel MID1/Yam8
MID1/Yam8: the stretch-activated, calcium-permeable nonselective cation channel of budding yeast (548 aa, Cch1 partner subunit), required for mating pheromone-induced Ca2+ influx; Yam8 is its fission yeast ortholog; unrelated to human or rice MID1 genes.
Striated muscle cell
A striated muscle cell is a muscle cell whose actin and myosin filaments are organized into sarcomeres, giving it a striped appearance; the two kinds are skeletal and cardiac.
Stromal cell
Stromal cell (CL:0000499): a mesenchymal-lineage connective tissue cell of the loose connective tissue forming an organ's supportive stroma; includes fibroblasts, pericytes, and mesenchymal stromal cells used in immunomodulatory therapy.
Stromal cell of endometrium
Stromal cells of endometrium, also called endometrial stromal fibroblasts, are the connective tissue cells of the uterine lining that drive its monthly remodeling and, during pregnancy, differentiate into decidual cells essential for embryo implantation.
Subtomogram averaging
Subtomogram averaging (STA), also called single particle tomography, is a computational method in structural biology that aligns and averages copies of macromolecular complexes extracted from cryo-electron tomograms.
SUM149PT
SUM149PT (CVCL_3422, RRID:CVCL_3422), also called SUM149, is a human triple-negative, BRCA1-mutant inflammatory breast cancer cell line derived from a primary invasive ductal carcinoma, used widely in IBC and TNBC drug research.
SUM159PT
SUM159PT (SUM-159, CVCL_5423) is a human triple-negative, claudin-low breast cancer cell line from an anaplastic pleomorphic carcinoma of a 71-year-old woman, with HRAS G12D, PIK3CA H1047L, TP53 mutations, used for estrogen-independent and invasive breast cancer research.
SUP-T1
SUP-T1 (SupT1, Stanford University Pediatric T-cell line 1, CVCL_1714, ATCC CRL-1942) is a human CD4+ T-lymphoblastic lymphoma cell line from an 8-year-old boy, widely used for HIV-1 research and T-ALL studies.
Super-resolution radial fluctuations
Super-resolution radial fluctuations (SRRF) is a fluorescence microscopy image-processing method, introduced in 2016, that reconstructs super-resolution images from fluorophore fluctuations at low excitation power, without structured illumination or single-molecule isolation.