The Arabidopsis root is a dynamic system where the interaction between different plant hormones controls root meristem activity and, thus, organ growth. In the root, a characteristic graded distribution of the hormone auxin provides positional information, coordinating the proliferating and differentiating cell status. The hormone cytokinin shapes this gradient by positioning an auxin minimum in the last meristematic cells. This auxin minimum triggers a cell developmental switch necessary to start the differentiation program, thus, regulating the root meristem size. To position the auxin minimum, cytokinin promotes the expression of the IAA-amidosynthase group II gene GH3.17, which conjugates auxin with amino acids, in the most external layer of the root, the lateral root cap tissue. Since additional GH3 genes are expressed in the root, we questioned whether cytokinin to position the auxin minimum also operates via different GH3 genes. Here, we show that cytokinin regulates meristem size by activating the expression of GH3.5 and GH3.6 genes, in addition to GH3.17. Thus, cytokinin activity provides a robust control of auxin activity in the entire organ necessary to regulate root growth.

Cytokinin-Dependent Control of GH3 Group II Family Genes in the Arabidopsis Root / Pierdonati, Emanuela; Unterholzner, Simon Josef; Salvi, Elena; Svolacchia, Noemi; Bertolotti, Gaia; Dello Ioio, Raffaele; Sabatini, Sabrina; Di Mambro, Riccardo. - In: PLANTS. - ISSN 2223-7747. - 8:4(2019). [10.3390/plants8040094]

Cytokinin-Dependent Control of GH3 Group II Family Genes in the Arabidopsis Root

Pierdonati, Emanuela;Salvi, Elena;SVOLACCHIA, NOEMI;BERTOLOTTI, GAIA;Dello Ioio, Raffaele;Sabatini, Sabrina;Di Mambro, Riccardo
2019

Abstract

The Arabidopsis root is a dynamic system where the interaction between different plant hormones controls root meristem activity and, thus, organ growth. In the root, a characteristic graded distribution of the hormone auxin provides positional information, coordinating the proliferating and differentiating cell status. The hormone cytokinin shapes this gradient by positioning an auxin minimum in the last meristematic cells. This auxin minimum triggers a cell developmental switch necessary to start the differentiation program, thus, regulating the root meristem size. To position the auxin minimum, cytokinin promotes the expression of the IAA-amidosynthase group II gene GH3.17, which conjugates auxin with amino acids, in the most external layer of the root, the lateral root cap tissue. Since additional GH3 genes are expressed in the root, we questioned whether cytokinin to position the auxin minimum also operates via different GH3 genes. Here, we show that cytokinin regulates meristem size by activating the expression of GH3.5 and GH3.6 genes, in addition to GH3.17. Thus, cytokinin activity provides a robust control of auxin activity in the entire organ necessary to regulate root growth.
2019
GRETCHEN HAGEN 3 (GH3) IAA-amido synthase group II; auxin; auxin conjugation; auxin minimum; cytokinin; lateral root cap; root apical meristem
01 Pubblicazione su rivista::01a Articolo in rivista
Cytokinin-Dependent Control of GH3 Group II Family Genes in the Arabidopsis Root / Pierdonati, Emanuela; Unterholzner, Simon Josef; Salvi, Elena; Svolacchia, Noemi; Bertolotti, Gaia; Dello Ioio, Raffaele; Sabatini, Sabrina; Di Mambro, Riccardo. - In: PLANTS. - ISSN 2223-7747. - 8:4(2019). [10.3390/plants8040094]
File allegati a questo prodotto
File Dimensione Formato  
Pierdonati_Cytokinin_2019.pdf

accesso aperto

Tipologia: Versione editoriale (versione pubblicata con il layout dell'editore)
Licenza: Creative commons
Dimensione 12.53 MB
Formato Adobe PDF
12.53 MB Adobe PDF

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11573/1275762
Citazioni
  • ???jsp.display-item.citation.pmc??? 14
  • Scopus 31
  • ???jsp.display-item.citation.isi??? 30
social impact