- Kinase
- Enzyme (i.e. a protein) that transfers phosphate groups (e.g. from ATP) to a substrate (i.e. another molecule). Used in signalling, cell cycle coordination. Most common type are protein kinases, which phosphorylate proteins (incl. enzymes, regulating their behaviour). Other types: lipid kinases, carbohydrate kinases. The opposite are phophotases, which reverse the process.
- Ligand
- Small molecule (typically an extracellular signal molecule) that forms a complex with a (large) biomolecule (typically a protein, the binding of which initiates a response in a cell). For example, GABA (an amino acid) binds to GABA receptors (proteins), transmitting signals between neurons (nerve cells). So it is a neurotransmitter. Other types exist too.
- Transcription factor
- DNA-binding protein that up- or down-regulates gene expression by controlling transcription (i.e. DNA->mRNA)
- Gene Set Enrichment Analysis (GSEA)
- Identifies gene sets (e.g. members of a specific GO (biological process) category, or a KEGG pathway) that are collectively significantly differentially expressed between two conditions (i.e. they all appear either near the top or bottom of a ranked list of over- or under-expressed genes between phenotypes). Note that this relies on having reference gene sets available.
See also: Molecular Biology of the Cell Glossary