Anoxia-enhanced expression of genes isolated by suppression subtractive hybridization from pondweed (Potamogeton distinctus A. Benn.) turions

Abstract

Pondweed (Potamogeton distinctus A. Benn.), a monocot aquatic plant species, has turions, which are overwintering buds forming underground as an asexual reproductive organ. Turions not only survive for more than one month but also elongate under strict anoxia, maintaining high-energy charge by activation of fermentation. We cloned 82 cDNA fragments of genes, that are up-regulated during anoxic growth of pondweed turions, by suppression subtractive hybridization. The transcript levels of 44 genes were confirmed to be higher under anoxia than those in air by both Northern blot analysis and a semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) method. A homology search for their nucleotide sequences revealed that some of them are highly homologous to known sequences of genes from other plants. They included alcohol dehydrogenase, pyruvate decarboxylase (PDC), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), vacuolar H(+)-translocating pyrophosphatase and a plasma membrane intrinsic protein. Time courses of transcript accumulation of some genes under anoxia were different from those in air. The activity of PDC increased under anoxic conditions but the activities of GAPDH and pyrophosphatase remained constant after anoxic treatment. Anoxically up-regulated genes are possibly involved in physiological events to control energy production, pH regulation and cell growth under anoxia. These results suggest that transcriptional regulation of these genes serves as an essential part of survival and growth of pondweed turions under anoxia.

The ability to regulate voltage-gated K+-permeable channels in the mature root epidermis is essential for waterlogging tolerance in barley

“…The opposite scenario occurs in the elongation zone. In this context, our results are consistent with previous reports ( Carystinos et al , 1995 ; Harada et al , 2007 ) of a massive increase in the transcript level of V-PPase after plant exposure to anoxic conditions followed by its decrease upon return to the well-aerated state. It should be noted that V-PPase activity shows a strong K + dependence ( Obermeyer et al , 1996 ).…”

Transcriptional responses to flooding stress in roots including hypocotyl of soybean seedlings

“…Benn.) has been reported as one of the anoxically up-regulated genes which are possibly involved in physiological events to control energy production, pH regulation and cell growth under anoxia (Harada et al 2007). The expressions of the FISs were rapidly and specifically induced by flooding in all organs of the soybean seedlings (Figs.…”

Efficient use of energy in anoxia‐tolerant plants with focus on germinating rice seedlings

“…Similarly, V‐H + PP i ase transcript was among 44 upregulated genes, including alcohol dehydrogenase (ADH) and pyruvate decarboxylase (PDC), observed in anoxic compared to aerated turions of Potamogeton distinctus . However, in that investigation changes in enzyme activity of V‐H + PP i ases and PDC, a key enzyme of ethanol formation, were small (Harada et al ., ).…”