1,440 articles
SK-N-BE(2)-C
SK-N-BE(2)-C (BE2C, CVCL_0529, ATCC CRL-2268) is a clonal subline of the SK-N-BE(2) human neuroblastoma cell line, MYCN-amplified with a TP53 C135F mutation, I-type phenotype, derived from a 1972 bone marrow metastasis.
SK-N-MC
SK-N-MC (ATCC HTB-10, CVCL_0530) is a human cell line established in 1971 from a supra-orbital metastasis of an Askin tumor; long mislabeled neuroblastoma, it is an Ewing sarcoma line carrying EWS-FLI1.
SK-N-SH
SK-N-SH (CVCL_0531, ATCC HTB-11) is a human neuroblastoma cell line established in 1970 from the bone marrow metastasis of a four-year-old girl at Memorial Sloan Kettering; parent of SH-SY5Y and SH-EP, with ALK F1174L and NRAS Q61K mutations.
SK-OV-3
SK-OV-3 (SKOV3), human ovarian cancer cell line, CVCL_0532, ATCC HTB-77, established 1973 at Memorial Sloan Kettering from ascites of a 64-year-old woman; epithelial, drug-resistant, most cited ovarian cancer line but a poor HGSOC model, likely clear cell origin.
Skeletal muscle myoblast
Skeletal muscle myoblast (skeletal myoblast, CL:0000515), a mononucleated progenitor that differentiates and fuses into multinucleate skeletal muscle fibers; derived embryonically from somites and postnatally from satellite cells.
Skeletal muscle satellite cell
The skeletal muscle satellite cell (myosatellite cell) is the resident stem cell of skeletal muscle, discovered in 1961 by Mauro and Katz, lying between basal lamina and sarcolemma, quiescent until activated to supply myoblasts for muscle growth and repair.
Skeletogenic cell
Skeletogenic cell (Cell Ontology CL:0007001): umbrella term for cells forming skeletal tissue, including osteoblasts, chondroblasts, and chondrocytes, arising from skeletal stem and progenitor cells in periosteum and bone marrow.
Skin fibroblast
Skin fibroblast, or dermal fibroblast, is the main connective tissue cell of the dermis, secreting collagen-rich extracellular matrix; heterogeneous papillary and reticular subtypes drive wound healing, scarring, hair follicle formation, and skin aging.
SKM-1
SKM-1 (also SKM1, CVCL_0098, DSMZ ACC 547) is a human acute myeloid leukemia cell line established in 1989 from a 76-year-old Japanese man with AML M5 following myelodysplastic syndrome, doubling in about 48 hours, with TP53 R248Q, TET2, and ASXL1 mutations, used to study MDS-to-AML progression.
Sliding filament theory
Sliding filament theory: the 1954 Huxley–Niedergerke and Huxley–Hanson model of muscle contraction in which actin and myosin filaments slide past each other, shortening sarcomeres without filament length change, powered by ATP-driven myosin cross-bridges and triggered by calcium.
Slow muscle cell
Slow muscle cell (slow-twitch, type I fiber): oxidative, fatigue-resistant skeletal muscle cell defined by MyHC I expression; soleus-rich, 10:5:1 power ratio versus fast fibers, high lipid storage, atrophy-resistant with aging.
Small kinetochore-associated protein
Small kinetochore-associated protein (SKAP, kinastrin, KNSTRN, UniProt Q9Y448) is a 316-aa microtubule plus-end tracking protein that partners with Astrin to stabilize bioriented kinetochore-microtubule attachments, reduce friction, and support mouse spermatogenesis.
Small nucleolar RNA
Small nucleolar RNA (snoRNA; SNORD/SNORA genes): short non-coding RNAs in the nucleolus that, as box C/D and H/ACA snoRNPs, guide rRNA 2'-O-methylation, pseudouridylation, and pre-rRNA cleavage.
Small ribosomal subunit protein uS9, bacteria/plastid
uS9, formerly bacterial S9 (E. coli rpsI; yeast S16), is a universal small ribosomal subunit protein of bacteria, plastids, and mitochondria; its C-terminal tail contacts P-site tRNA at the decoding center, and plastid RPS9 mutations cause embryo lethality in maize and rice.
Smooth muscle cell
Smooth muscle cell (SMC, CL:0000192): non-striated, spindle-shaped involuntary muscle cell with one central nucleus, 30-200 μm long, lining hollow organs and blood vessels; contracts via calmodulin-MLCK myosin phosphorylation and latch-bridge tone.
Smooth muscle cell apoptotic process
Smooth muscle cell apoptotic process (GO:0034390, SMC apoptosis): regulated programmed cell death in smooth muscle cells, central to vascular remodeling, atherosclerosis, aneurysm, and hypertension, and modulated by statins and antihypertensive drugs.
SMS-KAN
SMS-KAN (CVCL_7131) is a human neuroblastoma cell line established in 1978 from a pelvic primary tumor of a 36-month-old girl before therapy; its paired post-treatment line SMS-KANR came from the same patient's relapsed bone marrow, making the pair a before/after-chemotherapy model.
SMS-KCNR
SMS-KCNR (KCNR, CVCL_7134) is a human neuroblastoma cell line established in 1979 from bone marrow after chemotherapy, MYCN-amplified with ALK F1174L, paired with SMS-KCNR's pre-treatment counterpart SMS-KCNR's sister line SMS-KCN, and widely used in differentiation and drug-resistance research.
SNARE proteins
SNARE proteins, named for soluble NSF attachment protein receptors, are conserved eukaryotic membrane proteins whose four-helix bundle assembly pulls membranes together to drive vesicle fusion, from neurotransmitter release to endosomal trafficking.
SNB-19
SNB-19 (SNB19, Surgical Neurology Branch-19), human glioblastoma cell line CVCL_0535, NCI-60 panel member; STR profiling shows it is a U-251MG derivative, registered as misidentified ICLAC-00268.
SNU-1
SNU-1 (NCI-SNU-1, CVCL_0099, ATCC CRL-5971) is a human gastric adenocarcinoma cell line established in 1984 at Seoul National University from a primary stomach tumor; near-diploid, MSI-positive, suspension-growing, and widely used in cancer pharmacogenomics.
SOD2
SOD2 (MnSOD, manganese superoxide dismutase) is the human mitochondrial matrix enzyme, gene at 6q25.3, that dismutates superoxide into hydrogen peroxide and oxygen; knockout mice are nonviable.
Sodium channel
Sodium channels are transmembrane proteins, chiefly voltage-gated (NaV1.1-1.9) plus epithelial ENaC, that conduct Na+ to drive action potentials; targets of local anesthetics, antiarrhythmics, tetrodotoxin, and the 2025 pain drug suzetrigine.
Sodium leak channel NALCN
NALCN (sodium leak channel, non-selective; VGCNL1, Rb21) is a voltage-independent, TTX-resistant four-domain cation channel carrying the major neuronal sodium leak current, with UNC-79/UNC-80 subunits, linked to respiratory rhythm and channelopathies.
Sodium-calcium exchanger
The sodium-calcium exchanger (NCX, SLC8 family: NCX1/2/3) is a plasma-membrane antiporter exchanging 3 Na+ for 1 Ca2+ in most animal cells, distinct from K+-dependent NCKX (4Na+:1Ca2++K+); it extrudes Ca2+ rapidly at low affinity and is central to cardiac calcium cycling and digitalis action.
Sodium:alanine symporter
Sodium:alanine symporter (AgcS family, PF01235, TC 2.A.25): bacterial/archaeal secondary transporter coupling alanine or glycine uptake to Na+ influx; 11-helix LeuT fold; M. maripaludis AgcS structures 6CSE/6CSF show occluded state and substrate selectivity.
Soft agar assay
The soft agar assay is a cell biology method that grows cells suspended in semi-solid agar to test anchorage-independent growth, serving as an in vitro proxy for tumorigenic potential.
Somatic cell
Somatic cells are any body cells in an organism other than reproductive germ cells, such as skin or neurons, which contribute to the body and not offspring.
Sonoporation
Sonoporation is a delivery technique that uses ultrasound, usually with gas-filled microbubbles, to create transient pores in cell membranes so drugs, genes, proteins, and nanoparticles can enter living cells.
Sorting and assembly machinery
Sorting and assembly machinery (SAM, or TOB) is the mitochondrial outer membrane complex, built around the BamA homolog Sam50 with Sam35 and Sam37, that folds and inserts β-barrel proteins such as Tom40 and VDAC by β-barrel switching.