Identification and Gene Expression of Anaerobically Induced Enolase in Echinochloa phyllopogon and Echinochloa crus-pavonis

Abstract

Enolase (2-phospho-o-glycerate hydrolase, EC 4.2.1.1 1 ) has been identified as an anaerobic stress protein in Echinochloa oryzoides based on the homology of its interna1 amino acid sequence with those of enolases from other organisms, by immunological reactivity, and induction of catalytic activity during anaerobic stress. Enolase activity was induced 5-fold i n anoxically treated seedlings of three flood-tolerant species (E. oryzoides, Echinochloa phyllopogon, and rice [Oryza safiva 1.1) but not in the flood-intolerant species (Echinochloa crus-pavonis). A 540-bp fragment of the enolase gene was amplified by polymerase chain reaction from cDNAs of E. phyllopogon and maize (Zea mays L.) and used to estimate the number of enolase genes and to study the expression of enolase transcripts in E. phyllopogon, E. crus-pavonis, and maize. Southern blot analysis indicated that only one enolase gene is present in either E. phyllopogon or E. crus-pavonis. Three patterns of enolase gene expression were observed in the three species studied. In E. phyllopogon, enolase induction at both the mRNA and enzyme activity levels was sustained at all times with a further induction after 48 h of anoxia. I n contrast, enolase was induced in hypoxically treated maize root tips only at the mRNA level. In E. crus-pavonis, enolase mRNA and enzyme activity were induced during hypoxia, but activity was only transiently elevated. These results suggest that enolase expression in maize and E. crus-pavonis during anoxia are similarly regulated at the transcriptional level but differ in posttranslational regulation, whereas enolase is fully induced in E. phyllopogon during anaerobiosis.

Functional analyses of ethylene response factor JERF3 with the aim of improving tolerance to drought and osmotic stress in transgenic rice

“…Enolase (2-phospho-D-glycerate hydratase) is a key enzyme catalyzing the dehydration of 2-poly (D-glutamic acid (PGA) to phosphoenolpyruvic acid (PEP) in the glycolytic pathway (Fox et al 1995). An increased mRNA level of OsEnol occurs in different plant species in response to environmental stresses (Umeda and Uchimiya 1994;Yan et al 2005Yan et al , 2006.…”

Growth and energy status of arrowhead tubers, pondweed turions and rice seedlings under anoxic conditions

“…However, the inhibition of many aerobic proteins can never be recovered and results in death. The effects of anoxia on protein biosynthesis in anoxic‐tolerant plant species, namely, rice (Mocquot et al 1981; Mujer et al 1993) and Echinochloa species (Mujer et al 1993; Fox et al 1995), are known to be quite different from those in intolerant species. Protein biosynthesis in the tolerant species is temporarily and partially depressed immediately after anaerobic treatment, but then some of the aerobic proteins are synthesized again, accompanied by the synthesis of a special set of anaerobic proteins.…”

Characterisation of two wheat enolase cDNA showing distinct patterns of expression in leaf and crown tissues of plants exposed to low temperature

“…), wheat enolase is likely encoded by a multigene family. In rice, tomato and tobacco, DNA gel blot analysis has confirmed that enolase is encoded by multigene families (Van Der Straeten et al ., ), but only by a single‐copy gene in Echinocloa phyllopogon and Echinocloa crus‐pavonis (Fox et al ., ). On the basis of the 15 µg of digested genomic DNA resolved by gel electrophoresis, the plasmid standard size of 7.47 kb and the 1C DNA content of hexaploid wheat at 17.3 pg, the estimated plasmid amount equivalent to one copy of the enolase gene per haploid genome is 6.7 pg.…”