Anther-specific expression of mutated melon ethylene receptor gene Cm-ERS1/H70A affected tapetum degeneration and pollen grain production in transgenic tobacco plants. Plant Cell Rep

Gene Research Center, University of Tsukuba, Ten-nodai 1-1-1, Tsukuba 305-8572, Japan.
Plant Cell Reports (Impact Factor: 3.07). 10/2006; 25(9):936-41. DOI: 10.1007/s00299-006-0147-0
Source: PubMed


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.

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    • "At present, ethylene is suggested to be a mediator of PCD in plants (Woltering and others 1999). Introduction of a constitutively active form of the melon ethylene receptor into tobacco under the control of an anther-specific promoter was shown to cause a reduced number of pollen grains and delay in the PCD of tapetal cells (Takada and others 2006). Because ethylene is believed to be a key regulator of PCD (Gunawardena 2008), these observations suggest that ethylene is involved in the PCD of tapetal cells. "
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