1. an ornamental shrub. See buxus sempervirens.
2. accommodation for a single horse averaging 10 ft × 12 ft in dimensions. Called also loose box.
3. to mix groups of sheep (box them up).
4. a repeating sequence of nucleotides that forms a transcription or a regulatory signal.
- CAT b. — a sequence associated with polymerase II activity.
- Hogness b. — see Pribnow box (below).
- Pribnow b. — the sequence of 5 to 10 bases in the promotor region of Escherichia coli genes. It is a variant of a basic sequence TATAATG. See also TATA box (below).
- TATA b. — a eukaryotic DNA sequence usually TATAAATA, similar to the Pribnow box of Escherichia coli, occurring in the promotor region 25 to 30 bases upstream from the transcriptional start site and required for mRNA chain initiation.
