Question

What are some biological process that is influenced by promoter strength? Can you find a website that discusses this in detail?

Answer 1

Promoter strength have its importance in genetic engineering and synthetic biology. A promoter with a certain strength for one given RNA can often be reused for other RNAs. The strength of promoter is mostly determined by its nucleotide sequence. Many promoter libraries have been established experimentally by process. The theoretical methods to predict the strength of one promoter from its nucleotide sequence are desirable. Such methods may not only valuable in the design of promoter with specified strength, but can also be used for understanding the mechanism of promoter in gene transcription.

                                                  SOME BIOLOGICAL PROCESSES

1.Chloroplast promoter strength

Promoter strength can be estimated by measuring rates of transcription processes by chloroplasts. Run-on transcription assays with permeabilized .The other genes listed above were transcribed at rates about 20 times lower than the rrn gene and at 3–10 times lower than rbcL and psbA, suggest that their promoters are considerably weak. The initiation from the rbcL promoter is formed approximately 10-fold by an enhancer-like sequence located about 140 bp downstream of the ?10 element . Without the enhancing element the rbcL promoter is about as robust as, for example, the atpB promoter.

2.Promoter Architecture and Gene Susceptibility

Promoter architecture is important for selection of target genes. Genes significantly downregulated in two different colon cancer cell lines on miR-17-5p and miR-20a expression and with a canonical seed-match hexamer in the forward strand of the promoter regions. Of the 104 genes fulfilling this criteria, they can be focused on five genes at random, only four of which were susceptible to TGS upon introduction of pre-miRNAs or miRNA.In the case of yeast, siRNA-initiated silencing was observed at only a subset of target loci, which correlated with antisense transcription and overexpression of Swi6, the yeast homologue of HP1.The target sequence alone is not sufficient for the TGS, and other promoter characteristics are required for a TGS-permissive state.