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Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is a housekeeping protein which plays various roles in non-metabolic processes in addition to its role in glucose catabolism. There are several GAPDH isoforms in plant cells. In this study, we cloned the full-length cDNA encoding the isoform GAPC in two ecotypes of Leymus chinensis (Trin.) Tzvelev, gray-green type and yellow-green type. The LcGAPC sequence includes an open reading frame (ORF) of 1014 bp encoding 337 amino acids. The predicted molecular weight is 36.5 kDa, and the pI is 6.19. The mRNA expression of LcGAPC decreased at 24 h and then increased significantly after 7 d after 400 mmol/L NaCl stress. At 200 mmol/L mixed alkali stress (NaHCO 3 :Na 2 CO 3 ¼9:1), the LcGAPC expression level gradually increased as time increased in the two ecotypes of L. chinensis. The results suggested that LcGAPC is a stress-inducible gene that might play a role in the salt and alkali stress response. This study provided a basis to further study the mechanism of expression characteristics under salt and alkali stress conditions of L. chinensis. ARTICLE HISTORY

Phenylpropanoid metabolism is an important secondary metabolism pathway in plants. Lignin, as a secondary metabolite was produced by secondary metabolism pathway, plays important roles on disease resistance in plants. PAL, C4H, and CHS are key enzymes involved in the secondary metabolism pathway and critical on disease resistance. We hypothesize that the expression of key enzymes of secondary metabolism pathway will be affected by abnormal environmental conditions; therefore provide the resistance to severe environment for plant. In this study, we analysed the gene expressions of PAL, C4H, and CHS under higher temperature and infection of germ (Pseudoperonosporacubensis) in Cucumber JingChun No.4, which is highly resistant to downy mildew. The gene expressions were quantified by semi-quantitative RT-PCR. Our results showed that the expression of C4H was consistently higher and not affected by germ inoculation. However, the expressions of PAL and CHS were increased at 2 h and 25 h, respectively, after inoculating with germs. Interestingly, we found that the expressions of all these three genes were decreased with treatment of higher temperature. Our results demonstrated that PAL, C4H and CSH are important in secondary metabolism and affect the potential resistant ability of plant to various severe growing environments.

Music has a long history of healing or mitigating physical and mental illness in the clinical setting. We aimed to test changes in behavioral cognition and serum proteomics in rats undergoing music intervention (MI). The Morris water maze (MWM) was used to evaluate spatial learning and memory in rats. Serum protein expression profiling was examined using magnetic bead-based matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF-MS). MI improved spatial learning and memory in both male and female rats. Peak 1708.61 (m/z values) was significantly increased in MI females vs. female controls. Peak 3925.09 (m/z values) was significantly reduced in MI males versus male controls. The two differential serum peptide peaks (m/z values: 1708.61, 3925.09) were further sequence identified as regions of proteins Desmin and Acsm1. Western blot and immunofluorescence testing of Desmin expression showed consistent results on proteomics analysis. MI plays an important role in behavioral cognition and protein expression in rats. This study provides a foundation in proteomics that suggests that MI might improve spatial learning and memory ability.

Recent studies have confirmed that chlorophyllase (CLH), a long-found chlorophyll (Chl) dephytylation enzyme for initiating Chl catabolism, has no function in leaf senescence-related Chl breakdown. Yet, CLH is considered to be involved in fruit degreening and responds to external and hormonal stimuli. The purpose of this work was to elucidate in detail the biochemical, structural properties, and gene expression of four CLHs from the Solanum lycopersicum genome so as to understand the roles of Solanum lycopersicum chlorophyllases (SlCLHs). SlCLH1/4 were the predominantly expressed CLH genes during leaf and fruit development/ripening stages, and SlCLH1 in mature green fruit was modulated by light. SlCLH1/2/3/4 contained a highly conserved GHSXG lipase motif and a Ser-Asp-His catalytic triad. We identified Ser159, Asp226, and His258 as the essential catalytic triad by site-directed mutagenesis in recombinant SlCLH1. Kinetic analysis of the recombinant enzymes revealed that SlCLH1 had high hydrolysis activities against Chl a, Chl b, and pheophytin a (Phein a), but preferred Chl a and Chl b over Phein a; SlCLH2/3 only showed very low activity to Chl a and Chl b, while SlCLH4 showed no Chl dephytylation activity. The recombinant SlCLH1/2/3 had different pH stability and temperature optimum. Removal of the predicted N-terminal processing peptide caused a partial loss of activity in recombinant SlCLH1/2 but did not compromise SlCLH3 activity. These different characteristics among SlCLHs imply that they may have different physiological functions in tomato.