#phabulosa

[whats-in-a-sentence]

ARP genes function, at least in part, by helping maintain the repression of KNOX1 (KNOTTED1-LIKE HOMEOBOX) genes in the developing leaf (Figure 19.5A). (...) Expression of the HD-ZIP III genes, such as PHABULOSA (PHB), and PHAVOLUTA (PHV), is normally limited to the adaxial domains of the leaf primordia (see Figure 19.5A). (...) The expression of miR166 in abaxial regions of the leaf primordia has been shown to reduce PHB and PHV transcript levels, thus enabling normal abaxial patterns of development (Figure 19.5B). (...) KANADI genes and HD-ZIP III genes play antagonistic roles in adaxial-abaxial patterning in both leaves and vasculature (see Figure 19.5B). (...) In Arabidopsis, expression of YABBY genes marks the abaxial domain and marginal regions of primordial leaves (see Figure 19.5A). (...) YABBY transcription factors positively regulate a member of the WOX gene family, PRS (PRESSED FLOWER), which is expressed in the leaf margin and promotes blade outgrowth (see Figure 19.5B). (...) PRS- and WOX1-dependent blade outgrowth is, in part, mediated by an as yet unidentified mobile signal(s) processed by KLU, a cytochrome P450 monooxygenase (see Figure 19.5B). (...) Developing leaf primordia can be divided lengthwise into four main zones extending from the meristem: boundary meristem, lower-leaf zone, petiole, and blade (see Figure 19.5A). (...) The region of the leaf primordium destined to become the petiole is characterized by the expression of BOP (Blade on Petiole) genes, which encode transcriptional activators that are required to establish petiole identity in the proximal portion of the leaf in Arabidopsis (see Figure 19.5A). (...) This polarity results in the differentiation of xylem on the adaxial side of the leaf vein, and phloem on the abaxial side (see Figure 19.5).

"Plant Physiology and Development" int'l 6e - Taiz, L., Zeiger, E., Møller, I.M., Murphy, A.

#book quotes #plant physiology and development #nonfiction #textbook #knox1 #knotted like homeobox #arp #apurinic endonuclease redox protein #leaves #hd zip iii #phabulosa #phb #phavoluta #phv #mir166 #microrna #kanadi #leaf veins #vascular leaves #yabby #arabidopsis #wox #wuschel homeobox #prs #pressed flower #wox1 #klu #cytochrome #bop #blade on petiole