Reference "Rice Undeveloped Tapetum1 is a major regulator of early tapetum development"

Reference ID

11269

Title

Rice Undeveloped Tapetum1 is a major regulator of early tapetum development

Source

The Plant cell, 2005, vol. 17, pp. 2705-2722

Authors (9)

Jung-K-H	Han-M-J
Lee-Y-S	Kim-Y-W
Hwang-I	Kim-M-J
Kim-Y-K	Nahm-B-H
An-G

Abstract

The tapetum, the innermost of four sporophytic layers in the anther wall, comes
in direct contact with the developing male gametophyte and is thought to play a
crucial role in the development and maturation of microspores. Here, we report
the identification of rice (Oryza sativa) Undeveloped Tapetum1 (Udt1), which is
required for the differentiation of secondary parietal cells to mature tapetal
cells. T-DNA or retrotransposon Tos17 insertions in the Udt1 gene caused male
sterility. The anther walls and meiocytes of the mutants were normal during the
early premeiosis stage, but their tapeta failed to differentiate and became
vacuolated during the meiotic stage. In addition, meiocytes did not develop to
microspores, and middle layer degeneration was inhibited. Consequently, the
anther locules contained no pollen. The UDT1:green fluorescent protein fusion
protein was localized to the nucleus. This, together with its homology with
other basic helix-loop-helix proteins, suggests that UDT1 is a transcription
factor. DNA microarray analysis identified 958 downregulated and 267 upregulated
genes in the udt1-1 anthers, suggesting that Udt1 plays a major role in
maintaining tapetum development, starting in early meiosis.