The KNOTTED-like genes of peach (Prunus persica L. Batsch) are differentially expressed during drupe growth and the class 1 KNOPE1 contributes to mesocarp development. (August 2015)

• Record Type: Journal Article
• Authors: Testone, Giulio; Condello, Emiliano; Di Giacomo, Elisabetta; Nicolodi, Chiara; Caboni, Emilia; Rasori, Angela; Bonghi, Claudio; Bruno, Leonardo; Bitonti, Maria Beatrice; Giannino, Donato
• Is Part Of: Plant science. Volume 237(2015:Aug.)
• Page Start: 69
• Page End: 79
• Publication Date: 2015-08
• Subjects: KNOX transcription factors -- Class 1 KNOPE1 -- Peach -- Drupe development -- Mesocarp development -- Gibberellin synthesis genes; 18S 18S ribosomal RNA -- ACT2 actin2 -- BP BREVIPEDICELLUS -- CCoAOMT1 caffeoyl coenzyme A O-methyltransferase 1 -- DAFB days after full bloom -- DAG days after germination -- EF early flowering -- PF pollination/fertilization -- GA gibberellin -- GA20ox1 gibberellin 20 oxidase 1 -- GA3ox1 gibberellin 3-oxidase 1 -- KNOPEs peach KNOX genes -- KNOX KNOTTED-like homeobox transcription factors -- KNOX1 class 1 KNOX -- PpH3 histone3 -- PpXTH9 xyloglucan endotransglucosylase/hydrolase 9 -- RPII RNA polymerase II -- SAM shoot apical meristem -- STM SHOOTMERISTEMLESS -- TF transcription factors.; Botany -- Periodicals; Botanique -- Périodiques; 580
• DOI: 10.1016/j.plantsci.2015.05.005
• Languages: English
• ISSNs: 0168-9452

Abstract

Highlights: Peach KNOX genes show diversified transcription during drupe early growth stages. The class 1 KNOPE 1 mRNA differentially localizes in mesocarp cellular elements during S1. The KNOPE1 is down-regulated in expanding cells of mesocarp at late S1. The 35S:KNOPE1 Arabidopsis fruit shows GA synthesis gene repression and cell size decrease. Negative correlation between KNOPE1 and PpGA3ox1 occurs in mesocarp at S1 and S2. Abstract: The KNOTTED-like transcription factors (KNOX) contribute to plant organ development. The expression patterns of peach KNOX genes showed that the class 1 members act precociously (S1–S2 stages) and differentially during drupe growth. Specifically, the transcription of KNOPE1 and 6 decreased from early (cell division) to late (cell expansion) S1 sub-stages, whilst that of STMlike1, 2, KNOPE2, 2.1 ceased at early S1. The KNOPE1 role in mesocarp was further addressed by studying the mRNA localization in the pulp cells and vascular net at early and late S1. The message signal was first diffuse in parenchymatous cells and then confined to hypodermal cell layers, showing that the gene down-tuning accompanied cell expansion. As for bundles, the mRNA mainly featured in the procambium/phloem of collateral open types and subsequently in the phloem side of complex structures (converging bundles, ducts). The KNOPE1 overexpression in Arabidopsis caused fruit shortening, decrease of mesocarp cell size, diminution of vascular lignification together with the repression of the major gibberellin synthesis genes AtGA20ox1 and AtGA3ox1 . Negative correlation between the expression of KNOPE1 and PpGA3ox1 was observed in four cultivars at S1, suggesting that the KNOPE1 repression of PpGA3ox1 may regulate mesocarp differentiation by acting on gibberellin homeostasis.