English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Background  Mutations in the  FRY1/SAL1  Arabidopsis locus are highly pleiotropic, affecting drought tolerance, leaf shape and root growth.  FRY1  encodes a nucleotide phosphatase that  in vitro  has inositol polyphosphate 1-phosphatase and 3′,(2′),5′-bisphosphate nucleotide phosphatase activities. It is not clear which activity mediates each of the diverse biological functions of FRY1  in planta .    Principal Findings  A  fry1  mutant was identified in a genetic screen for Arabidopsis mutants deregulated in the expression of  P i  H igh affinity  T ransporter 1;4 ( PHT1;4 ). Histological analysis revealed that, in roots,  FRY1  expression was restricted to the stele and meristems. The  fry1  mutant displayed an altered root architecture phenotype and an increased drought tolerance. All of the phenotypes analyzed were complemented with the  AHL  gene encoding a protein that converts 3′-polyadenosine 5′-phosphate (PAP) into AMP and Pi. PAP is known to inhibit exoribonucleases (XRN)  in vitro . Accordingly, an  xrn  triple mutant with mutations in all three XRNs shared the  fry1  drought tolerance and root architecture phenotypes. Interestingly these two traits were also complemented by grafting, revealing that drought tolerance was primarily conferred by the rosette and that the root architecture can be complemented by long-distance regulation derived from leaves. By contrast,  PHT1  expression was not altered in  xrn  mutants or in grafting experiments. Thus,  PHT1  up-regulation probably resulted from a local depletion of Pi in the  fry1  stele. This hypothesis is supported by the identification of other genes modulated by Pi deficiency in the stele, which are found induced in a  fry1  background.    Conclusions/Significance  Our results indicate that the 3′,(2′),5′-bisphosphate nucleotide phosphatase activity of FRY1 is involved in long-distance as well as local regulatory activities in roots. The local up-regulation of  PHT1  genes transcription in roots likely results from local depletion of Pi and is independent of the XRNs.

A Novel fry1 Allele Reveals the Existence of a Mutant Phenotype Unrelated to 5′->3′ Exoribonuclease (XRN) Activities in Arabidopsis thaliana Roots