Plant Physiol, December 1999, Vol. 121, pp. 1103-1116
Genes Expressed in Pinus radiata Male Cones
Include Homologs to Anther-Specific and Pathogenesis Response
Genes1
Adrian R.
Walden,
Christian
Walter,* and
Richard C.
Gardner
School of Biological Sciences, University of Auckland, Private Bag
92019, Auckland, New Zealand (A.R.W., R.C.G.); and New Zealand Forest
Research Institute, Private Bag 3020, Rotorua, New Zealand (A.R.W.,
C.W.)
We describe the isolation and
characterization of 13 cDNA clones that are differentially expressed in
male cones of Pinus radiata (D. Don). The transcripts of
the 13 genes are expressed at different times between meiosis and
microspore mitosis, timing that corresponds to a burst in tapetal
activity in the developing anthers. In situ hybridization showed that
four of the genes are expressed in the tapetum, while a fifth is
expressed in tetrads during a brief developmental window. Six of the
seven cDNAs identified in database searches have striking similarity to
genes expressed in angiosperm anthers. Seven cDNAs are homologs of
defense and pathogen response genes. The cDNAs identified are predicted
to encode a chalcone-synthase-like protein, a thaumatin-like protein, a
serine hydrolase thought to be a putative regulator of programmed cell
death, two lipid-transfer proteins, and two homologs of the anther-specific A9 genes from Brassica napus and
Arabidopsis. Overall, our results support the hypothesis that many of
the reproductive processes in the angiosperms and gymnosperms were
inherited from a common ancestor.
1
A.R.W. was supported by a doctoral grant from
the New Zealand Forest Research Institute. The project was
funded by the New Zealand Foundation for Research Science and Technology.
*
Corresponding author; e-mail walterc{at}fri.cri.nz; fax
64-7-347-9380.
© 1999 American Society of Plant Physiologists
