The important issue of photoreactivation DNA repair in plants has become even more interesting in recent years because a family of genes that are highly homologous to photoreactivating DNA repair enzymes but that function as blue light photoreceptors has been isolated. Here, we report the isolation of a novel photolyase-like sequence from Arabidopsis designated PHR1 (for photoreactivating enzym...

HOTOREACTIVATION is the reversal by near-ultraviolet or visible light of 'ultraviolet radiation damage to biological systems ( JAGGER 1958). This phenomenon has been demonstrated in the intact cell in a spectrum of organisms (extending from bacteria to mammals) (JAGGER 1958) and in vitro with ultravioletinactivated transforming factor (deoxyribose nucleic acid) of Hemophilus in@uenzae ( GOODGAL...

The quantum yield, under non-photoreactivating conditions, for inactivation of tobacco mosaic virus RNA by ultraviolet radiation (254 nm.) is independent of the RNA concentration but varies appreciably with the ionic strength of the irradiation solvent, being approximately three times greater in water than in o-I M-potassium phosphate buffer. Photoreactivation of inactivated tobacco mosaic viru...

Photoreactivation is the repair of ultraviolet radiation damage in a biological system with light of wavelength longer than that of the damaging radiation (Jagger1). A wide variety of ultraviolet induced effects may be reversed by photoreactiva­ tion, including killing, mutations, division delay, block in the DNA synthesis, etc. Such photoreactiva­ tion effects generally involve the photoenzyma...

Incubation of UV-irradiated plasmid DNA with a protein extract prepared from Escherichia coli cells led to the production of mutations in the cro gene residing on the plasmid. The mutations were detected in a subsequent bioassay step, which involved transformation of an indicator strain with the plasmid DNA that was retrieved from the reaction mixture, followed by plating on lactose/MacConkey p...

In vitro selection was used to investigate whether nucleic acid enzymes are capable of catalyzing photochemical reactions. The reaction chosen was photoreactivation of thymine cyclobutane dimers in DNA by using serotonin as cofactor and light of wavelengths longer than the absorption spectrum of DNA. Curiously, the dominant single-stranded DNA sequence selected, UV1A, was found to repair its in...