Anaerobic treatment dramatically alters the pattern of gene expression
in maize (Zea mays L.) seedlings, During anaerobiosis there is an imm
ediate repression of pre-existing protein synthesis and the simultaneo
us selective synthesis of four polypeptides with a molecular weight of
similar to 33 kDa (the transition polypeptides), After 90 min, this i
s followed by specific transcription and mRNA accumulation as well as
the selective synthesis of approximately 20 anaerobically-induced prot
eins, Among these anaerobic proteins (ANPs) are enzymes involved in gl
ycolysis and related processes, such as alcohol dehydrogenase (ADH) al
dolase, enolase, glucose-phosphate isomerase, glyceraldehyde-3-phospha
te dehydrogenase, pyruvate decarboxylase, and sucrose synthase, Howeve
r, two genes, inducible by oxygen deprivation, have been found that ha
ve different functions, One that has homology to xyloglucan endotransg
lycosylase may be involved in aerenchyma formation during flooding, Th
e anaerobic response is most likely a plant's natural reaction to floo
ding, A similar condition has been observed in every plant species ana
lysed to date. The anaerobic response and flooding tolerance in maize
has been analysed using a combination of molecular, biochemical and ge
netic approaches, The studies include the characterization of anaerobi
cally inducible genes, the identification of genes involved in floodin
g tolerance, and analysis of the signal transduction events that are i
nvolved in the perception of oxygen deprivation and lead to the anaero
bic response.