Second-step splicing factors and heavy metal stress management in Arabidopsis thaliana
type: CreativeWork
description: Pre-mRNA splicing in plants is mechanistically the same as splicing in other eukaryotes, but its mode of intron recognition is unique. Whereas in animals a pyrimidine-tract contributes to the definition of exons, in plants, introns are defined by the boundaries of AU-rich intron and GC-rich exon. Some of these differences may depend on splicing factors mediating recognition of the unusual sequence-dependent transition points and/or factors mediating the first- and second-steps in intron definition and excision. The second transesterification step of splicing involves many protein factors (second-step splicing factors) that have not been previously characterized in Arabidopsis. Among these are numerous genes encoded by multicopy genes in this model plant: PRP16 (1 copy), PRP17 (2 copies), PRP18 (2 copies), PRP22 (3 copies) and SLU7 (3 copies). This work is aimed at defining the structural differences and expression patterns of these multiple second-step splicing factors and their involvements in heavy metal stress response. The first goal of this project was to determine unique characteristics of the multicopy second-step splicing factors and the tissue and developmental stages in which each of these genes is expressed. My studies have indicated that all of these second-step splicing factors genes are expressed in Arabidopsis. While most are constitutively expressed throughout each tissue type and developmental stage, a specialized subset including PRP17-2, PRP18B, PRP22-3 and SLU7-2 are primarily expressed in flower and silique tissue in four-week-old plants and throughout the entire seven-week-old plant. Each of these specialized genes has unique structural features when compared to their homologs, suggesting that they form unique spliceosomal networks. These include variations in sequence identity between each other and their homologs in other organisms. Additionally, homology modeling revealed specific sites in which changes in residues will likely contribute to …
abstract: Pre-mRNA splicing in plants is mechanistically the same as splicing in other eukaryotes, but its mode of intron recognition is unique. Whereas in animals a pyrimidine-tract contributes to the definition of exons, in plants, introns are defined by the boundaries of AU-rich intron and GC-rich exon. Some of these differences may depend on splicing factors mediating recognition of the unusual sequence-dependent transition points and/or factors mediating the first- and second-steps in intron definition and excision. The second transesterification step of splicing involves many protein factors (second-step splicing factors) that have not been previously characterized in Arabidopsis. Among these are numerous genes encoded by multicopy genes in this model plant: PRP16 (1 copy), PRP17 (2 copies), PRP18 (2 copies), PRP22 (3 copies) and SLU7 (3 copies). This work is aimed at defining the structural differences and expression patterns of these multiple second-step splicing factors and their involvements in heavy metal stress response. The first goal of this project was to determine unique characteristics of the multicopy second-step splicing factors and the tissue and developmental stages in which each of these genes is expressed. My studies have indicated that all of these second-step splicing factors genes are expressed in Arabidopsis. While most are constitutively expressed throughout each tissue type and developmental stage, a specialized subset including PRP17-2, PRP18B, PRP22-3 and SLU7-2 are primarily expressed in flower and silique tissue in four-week-old plants and throughout the entire seven-week-old plant. Each of these specialized genes has unique structural features when compared to their homologs, suggesting that they form unique spliceosomal networks. These include variations in sequence identity between each other and their homologs in other organisms. Additionally, homology modeling revealed specific sites in which changes in residues will likely contribute to …
author: Glekas, Amy
language: en
keywords: Arabidopsis, pre-mRNA splicing factors, heavy metal stress, Ser/Arg-rich protein, second-step splicing factors
date published: 2013-08-22T16:47:38Z
date modified: 2026-07-22T22:25:36Z
provider: University of Illinois - Urbana-Champaign
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Illinois at Urbana-Champaign

PropertyValue
property ID: Handle
value: http://hdl.handle.net/2142/45555