Tissue-specific auxin signaling in response to temperature fluctuation.

Auxin levels are well regulated in cells and tissues by both transport and local biosynthesis, and its distribution is important for the modulation of cell proliferation, differentiation, development, tropisms and high-temperature response. Activation of auxin biosynthesis with increased temperatures reported in certain plant tissues. In contrast, our studies indicated that male tissue-specific auxin reduction via transcriptional repression of the YUCCA auxin biosynthesis genes is the primary cause of high temperature injury, which leads the abortion of pollen development in Arabidopsis and barley Hordeum vulgare L. Furthermore, the abortion can be reversed by the application of exogenous auxin, suggesting that the application may maintain crop yields during the current global warming crisis.