Reactive oxygen species modulate the differential expression of methionine sulfoxide reductase genes in Chlamydomonas reinhardtii under high light illumination.

Illumination of Chlamydomonas reinhardtii cells at 1000 (high light, HL) or 3000 (very high light, VHL) µmol photons m(-2)  s(-1) intensity increased superoxide anion radical (O(2)(•-)) and hydrogen peroxide (H(2)O(2)) production, and VHL illumination also increased the singlet oxygen ((1)O(2)) level. HL and VHL illumination decreased methionine sulfoxide reductase A4 (CrMSRA4) transcript levels but increased CrMSRA3, CrMSRA5 and CrMSRB2.1 transcripts levels.

Implications of the up-regulation of genes encoding protein degradation enzymes and heat shock protein 90 for intertidal green macroalga Ulva fasciata against hypersalinity-induced protein oxidation.

The molecular acclimation of intertidal green macroalga Ulva fasciata Delile to high salinity stress were examined by the construction of a forward cDNA library via the suppressive subtractive hybridization between 30‰ and 90‰ (24 h) and by the time course dynamics of several abundantly expressed genes. Among the genes with known sequences, the expressed sequence tags are abundant in the function of protein synthesis (ribosomal protein) and destination. The cDNAs of ATP-dependent Clp protease (UfClpC), 20S proteasome β-subunit type 1 domain (UfPbf1), ubiquitin-conjugating enzyme E2 I (UfUbc9), and heat shock protein 90A (UfHsp90A) were cloned.