Difference between revisions of "Part:BBa K4192141"

Latest revision as of 14:56, 12 October 2022

yf1(N37C)

The gene yf1 encodes a fusion kinase.The kinase YF1 ecxpressed controls gene expression in a light-dependent manner in vivo.The YF1 N37C can induce the expression of more downstream genes in the dark environment.

Usage

As an indispensable part of the light control system, Yf1 affects the phosphorylation of FixJ and then regulates the transcription of downstream genes by regulating the activity of the promoter.The YF1-containing light control system was introduced into the engineered bacteria to make them light-responsive and could be manipulated by light in a spatially and temporally accurate, reversible and non-harmful way.^[1]The N37C mutation of yf1 has a better effect on regulation, that is, more target genes can be expressed under light conditions, and leakage expression can be minimized under light conditions.

Biology

YF1 is a fusion protein coming from the heme-binding PAS sensor domain of FixL from Bradyrhizobium japonicum being replaced by light-oxygen-voltage (LOV) blue light sensor domain of Bacillus subtilis YtvA.Yf1 includes a light sensor subdomain and an effector subdomain. The light sensor binds a flavin chromophore. It absorbs light and influences effectors to be biologically active.The N37C mutation is located at a residue near the nonpolar dimethylbenzene portion of the flavin chromophore. This mutation allows YF1 to have a higher dynamic regulatory range. Additionally, the mutation of N37C in the LOV domain does not affect the way it responds to light and accelerates the dark recovery rate.^[2] Compared with other mutations, which have unnecessary and adverse effects on the regulation of light and lead to the reduction of absolute light responsiveness, N37C mutation has little effect on absolute light responsiveness, that is, it does not affect the apparent quantum yield.
^[3]

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Fig.1 Activity measurements of YF1 variants with the pDusk-DsRed reporter system.
The white bars are in light conditions and the black bars are in dark conditions.)^[3]

References

• Möglich, A., R.A. Ayers and K. Moffat, Design and Signaling Mechanism of Light-Regulated Histidine Kinases. Journal of Molecular Biology, 2009. 385(5): p. 1433-1444.
• Raffelberg, S., et al., The amino acids surrounding the flavin 7a-methyl group determine the UVA spectral features of a LOV protein. bchm, 2013. 394(11): p. 1517-1528.
• Diensthuber, R.P., et al., Biophysical, Mutational, and Functional Investigation of the Chromophore-Binding Pocket of Light-Oxygen-Voltage Photoreceptors. ACS Synthetic Biology, 2014. 3(11): p. 811-819.

Sequence and Features