Gene expression
Three gene cassettes are present: Nicotiania tabacum acetolactate synthase (ALS; acetohydroxy acid synthase), Petunia hybrida dihydroflavonol-4-reductase (DFR) and Viola sp. flavonoid3', 5'-hydroxylase (F3'5'H).

Transcription of ALS is under control of a Cauliflower mosaic virus (CaMV) 35S promoter and a N. tabacum ALS terminator. A 5' untranslated leader sequence from P. hybrida chlorophyll a/b-binding protein is also present at the 5' end of ALS, but is not expected to be translated. The leader sequence promotes high levels of transcription of ALS.

Transcription of DFR is under control of its endogenous promoter and terminator. The coding sequence contains 6 exons and 5 introns.

Transcription of F3'5'H is under control of an Antirrhinum majus chalcone synthase promoter and a P. hybrida D8 terminator.

Note:
- The size of the ALS coding sequence includes the size of the terminator (3.76 kb = size of ALS coding sequence + ALS terminator)
- The size of the DFR coding sequence represents the size of the full genomic cone (4.96 kb = DFR promoter + DFR coding sequence + DFR terminator)
- The T-DNA is present at one integration locus and contains one copy of each T-DNA component as determined by Southern blot analysis

There are up to five copies of each integrated component of the T-DNA, and integration of T-DNA has occurred at four loci. Estimated copy numbers of T-DNA components integrated in transgenic line FLO-4Ø685-1 as follows: LB - 2 copies, NtALS (SurB) - 2 copies, VhF3'5'H - 4 copies, PhDFR - 2 copies, RB - 5 copies.