Lambda Repressor. The repressor molecule of the Lambda bacteriophage binds not only to the OR1 site to prevent Cro transcription, but also to OR2, where it aids the binding of RNA polymerase to the repressor promoter. In fact a repressor dimer bound to OR1 interacts cooperatively with a second dimer binding to OR2.
Mandevillas grow as tropical perennials in frost-free regions. When looking for an attractive, blooming tropical vine, don't overlook mandevillas (Mandevilla spp.). These lovely climbing vines have abundant and showy blossoms that are produced for a period of several months.n these areas, mandevilla vines can reach a height of 10 to 20 feet, with older stems becoming woody and thick. In parts of zone 8 where winter frosts might occur, mandevillas planted outdoors often die back to the ground but regrow from surviving roots the next spring.
more varieties for Potentilla. (Potentilla fruticosa 'Abbotswood') bears white flowers and blue-green foliage on a shrub that grows 3 feet tall and 4 feet wide. Zones 3-7. (Potentilla fruticosa 'Daydawn') bears soft-yellow flowers suffused with pink on a compact, 4-foot-tall-and-wide shrub.Zones 3-7. (Potentilla fruticosa 'Klondike') is a sunny presence in the garden. It combines bright green leaves and yellow flowers and grows 3 feet tall and 5 feet wide.otentilla. Crisp, neat foliage and charming flowers that resemble anemones, in a broad color range, ensure that potentilla always has something going in the garden. Flowers bloom over a long period of time from late spring to autumn. When the leaves drop in fall, a reddish peeling bark is revealed.