Phytohormone abscisic acid (ABA) regulates many aspects of plant development and growth. To explore the molecular mechanism of ABA, we identified the novel ABA-regulated genes in Arabidopsis thaliana by searching for genes possessing two or more ABREs (ABA-responsive elements). One of these genes, two or more ABREs-containing gene 2 (TMAC2) is highly induced by ABA and NaC1. Database searches revealed that TMAC2 encodes a protein with no domains of known function. Expression of TMAC2-GFP fusion protein in Arabidopsis mesophyll protoplasts indicated that TMAC2 is targeted to the nucleus. Although the gene has a basal level of expression in various Arabidopsis organs/tissues except for adult leaves, a high expression level was detected in roots. Constitutive overexpression of TMAC2 in plants resulted in the insensitivity to ABA and NaCl, suggesting that TMAC2 plays a negative role in ABA and salt stress responses. Furthermore, TMAC2-overexpressing plants exhibited the short roots, late flowering and starch-excess phenotypes. RT-PCR analysis showed that decreased expression of two floral- and one starch degradation-related genes, SOC1/AGL20 and SEP3/AGL9, and SEX1, respectively, may lead to altered phenotypes of TMAC2-overexpressing plants. Taken together, our data reveal that TMAC2 acts in the nucleus and is an important negative regulator of ABA and salt stress responses, and could play a critical role in controlling root elongation, floral initiation and starch degradation.
A quick and simple method for establishing permanent rumimal fistulae is described. A frozen cannula is forced into the rumen in a manner similar to the use of a trocar. Minimal equipment is required, and the entire operation can be performed in 15 to 20 min in sheep or 30 min in cattle. The technique has been used successfully to fistulate seven sheep and two cows.
Thraustochytrids are heterotrophic fungus-like protists that can dissolve organic matters with enzymes. Four strains, AP45, ASP1, ASP2, and ASP4, were isolated from the coastal water of Taiwan, and respectively identified as Aurantiochytrium sp., Schizochytrium sp., Parietichytrium sp., and Botryochytrium sp. based on 18S rRNA sequences. Transcriptome datasets of these four strains at days 3-5 were generated using Next Generation Sequencing technology, and screened for enzymes with potential industrial applications. Functional annotations based on KEGG database suggest that many unigenes of all four strains were related to the pathways of industrial enzymes. Most of all four strains contained homologous genes for 15 out of the 17 targeted enzymes, and had extra-and/or intra-cellular enzymatic activities, including urease, asparaginase, lipase, glucosidase, alkaline phosphatase and protease. Complete amino sequences of the first-time identified L-asparaginase and phytase in thraustochytrids were retrieved, and respectively categorized to the Type I and BPPhy families based on phylogenetic relationships, protein structural modeling and active sites. Milligram quantities of highly purified, soluble protein of urease and L-asparaginase were successfully harvested and analyzed for recombinant enzymatic activities. These analytical results highlight the diverse enzymes for widerange applications in thraustochytrids.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.