Anther-specific expression of mutated melon ethylene receptor gene Cm-ERS1/H70A affected tapetum degeneration and pollen grain production in transgenic tobacco plants.
To develop a new system for inducible male sterility without any modification of the floral architecture in tobacco plants, a mutated ethylene receptor gene Cm-ERS1/H70A was fused either to the tobacco Nin88 promoter known to function mainly in the tapetum and microspore or to the CaMV 35S promoter known to be a constitutive promoter. The fusion genes pNin88::Cm-ERS1/H70A and p35S::Cm-ERS1/H70A were introduced in tobacco plants, which generated two independent transformants. Transformants with 35S::Cm-ERS1/H70A produced less normal pollen and had modified floral architecture while those with Nin88::Cm-ERS1/H70A produced less normal pollen without modification of floral architecture. Histological observations of anthers at stage 2 showed that tapetum degeneration in NH70A #8 and H70A #2 transformants occurred later than in wild types, strongly indicating that the expression of the mutated gene was involved in this delay. These results suggest that the tapetum-specific expression of a mutated ethylene receptor gene is a potential strategy for inducing male sterility in transgenic plants.
Gene Research Center, University of Tsukuba, Ten-nodai 1-1-1, Tsukuba 305-8572, Japan.
Keita
K
Takada
Kentaro
K
Ishimaru
Hiroshi
H
Kamada
Hiroshi
H
Ezura
D019662:Cucurbitaceae / Q000235:genetics* / Q000378:metabolism; D035264:Flowers / Q000166:cytology / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D009154:Mutation / Q000235:genetics*; D009928:Organ Specificity; D010940:Plant Proteins / Q000235:genetics*; D030821:Plants, Genetically Modified; D011058:Pollen / Q000378:metabolism*; D011956:Receptors, Cell Surface / Q000235:genetics*; D012639:Seeds / Q000378:metabolism; D014026:Nicotiana / Q000235:genetics / Q000502:physiology*
D010940:Plant Proteins; D011956:Receptors, Cell Surface; C083750:ethylene receptors, plant