Two mutants of Arabidopsis thaliana that are resistant to growth inhibition by indole-3-acetic acid (IAA)-phenylalanine have been isolated. Both mutants were 2- to 3-fold more resistant than wild type to inhibition by IAA-phenylalanine, IAA-alanine, and IAA-glycine in root growth assays. The mutant icr1 (but not icr2) also shows some resistance to IAA-aspartate. Studies using 3H-labeled IAA-phenylalanine showed that the uptake of conjugate from the medium by icr1 was the same as wild type and was reduced by about 25% in icr2. No differences in hydrolysis of the exogenous conjugate were detected between the mutants and their wild-type parents. There was no significant metabolism of the IAA released from the [3H]IAA-phenylalanine, whereas exogenous [3H]IAA was rapidly metabolized to two unidentified products considerably more polar than IAA. Analysis of a cross between icr1 and icr2 indicated that these mutations were at distinct loci and that their effects were additive, and preliminary mapping data indicated that icr1 and icr2 were located at the top and bottom of chromosome V, respectively.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC157998PMC
http://dx.doi.org/10.1104/pp.112.2.735DOI Listing

Publication Analysis

Top Keywords

icr1 icr2
12
mutants arabidopsis
8
arabidopsis thaliana
8
growth inhibition
8
wild type
8
isolation characterization
4
mutants
4
characterization mutants
4
thaliana increased
4
increased resistance
4

Similar Publications

Arterial spin-labeling magnetic resonance imaging (ASL-MRI) is widely used for evaluating collateral development in patients with acute ischemic stroke (AIS). This study aimed to characterize the findings of multiphase ASL-MRI between embolic and atherosclerotic large vessel occlusion (LVO) to aid in the differential diagnosis. Among 982 patients with AIS, 44 who were diagnosed with acute, symptomatic, and unilateral occlusion of the horizontal segment of the middle cerebral artery (MCA) were selected and categorized into embolic stroke (ES) and atherosclerosis (AT) groups.

View Article and Find Full Text PDF

Dynamic methylation pattern of H19DMR and KvDMR1 in bovine oocytes and preimplantation embryos.

J Assist Reprod Genet

February 2024

Department of Genetics, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, 14049-900, Brazil.

Purpose: This study aimed to evaluate the epigenetic reprogramming of ICR1 (KvDMR1) and ICR2 (H19DMR) and expression of genes controlled by them as well as those involved in methylation, demethylation, and pluripotency.

Methods: We collected germinal vesicle (GV) and metaphase II (MII) oocytes, and preimplantation embryos at five stages [zygote, 4-8 cells, 8-16 cells, morula, and expanded blastocysts (ExB)]. DNA methylation was assessed by BiSeq, and the gene expression was evaluated using qPCR.

View Article and Find Full Text PDF

Immunologic constant of rejection as a predictive biomarker of immune checkpoint inhibitors efficacy in non-small cell lung cancer.

J Transl Med

September 2023

Multidisciplinary Oncology and Therapeutic Innovations Department, Aix Marseille Univ, APHM, INSERM, CNRS, CRCM, Hôpital Nord, Marseille, France.

Article Synopsis
  • Anti-PD1/PDL1 immune checkpoint inhibitors have improved outcomes for advanced non-small cell lung cancer (NSCLC) patients, but response rates are low and potential for severe side effects makes biomarker identification necessary.
  • Researchers analyzed gene expression in 44 NSCLC tumors treated with ICI, combining this with data from four public datasets to evaluate the Immunologic Constant of Rejection (ICR) as a predictor of clinical benefit.
  • The study found that certain ICR classifications were significantly associated with higher rates of Durable Clinical Benefit (DCB) from treatment, suggesting that the 20-gene ICR signature could serve as an independent biomarker for predicting response to anti-PD1/PDL1 therapy.
View Article and Find Full Text PDF

Embryonic tumors share few recurrent mutations, suggesting that other mechanisms, such as aberrant DNA methylation, play a prominent role in their development. The loss of imprinting (LOI) at the chromosome region 11p15 is the germline alteration behind Beckwith-Wiedemann syndrome that results in an increased risk of developing several embryonic tumors. This study analyzed the methylome, using EPIC Beadchip arrays from 99 sporadic embryonic tumors.

View Article and Find Full Text PDF

Optical genome mapping (OGM) appears as a new tool for matching standard cytogenetic methods (karyotype and microarray) into a single assay. The chromosomal region 11p15.5 harbours two differentially methylated regions, the imprinting centre regions 1 and 2 (ICR1, ICR2).

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!