Dataset Information

Bioinformatics analysis of alternative polyadenylation in green alga Chlamydomonas reinhardtii using transcriptome sequences from three different sequencing platforms.

ABSTRACT: Messenger RNA 3'-end formation is an essential posttranscriptional processing step for most eukaryotic genes. Different from plants and animals where AAUAAA and its variants routinely are found as the main poly(A) signal, Chlamydomonas reinhardtii uses UGUAA as the major poly(A) signal. The advance of sequencing technology provides an enormous amount of sequencing data for us to explore the variations of poly(A) signals, alternative polyadenylation (APA), and its relationship with splicing in this algal species. Through genome-wide analysis of poly(A) sites in C. reinhardtii, we identified a large number of poly(A) sites: 21,041 from Sanger expressed sequence tags, 88,184 from 454, and 195,266 from Illumina sequence reads. In comparison with previous collections, more new poly(A) sites are found in coding sequences and intron and intergenic regions by deep-sequencing. Interestingly, G-rich signals are particularly abundant in intron and intergenic regions. The prevalence of different poly(A) signals between coding sequences and a 3'-untranslated region implies potentially different polyadenylation mechanisms. Our data suggest that the APA occurs in about 68% of C. reinhardtii genes. Using Gene Ontolgy analysis, we found most of the APA genes are involved in RNA regulation and metabolic process, protein synthesis, hydrolase, and ligase activities. Moreover, intronic poly(A) sites are more abundant in constitutively spliced introns than retained introns, suggesting an interplay between polyadenylation and splicing. Our results support that APA, as in higher eukaryotes, may play significant roles in increasing transcriptome diversity and gene expression regulation in this algal species. Our datasets also provide useful information for accurate annotation of transcript ends in C. reinhardtii.

SUBMITTER: Zhao Z

PROVIDER: S-EPMC4025486 | biostudies-literature | 2014 Mar

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Bioinformatics analysis of alternative polyadenylation in green alga Chlamydomonas reinhardtii using transcriptome sequences from three different sequencing platforms.

Zhao Zhixin Z Wu Xiaohui X Kumar Praveen Kumar Raj PK Dong Min M Ji Guoli G Li Qingshun Quinn QQ Liang Chun C

G3 (Bethesda, Md.) 20140313 5

Messenger RNA 3'-end formation is an essential posttranscriptional processing step for most eukaryotic genes. Different from plants and animals where AAUAAA and its variants routinely are found as the main poly(A) signal, Chlamydomonas reinhardtii uses UGUAA as the major poly(A) signal. The advance of sequencing technology provides an enormous amount of sequencing data for us to explore the variations of poly(A) signals, alternative polyadenylation (APA), and its relationship with splicing in th ...[more]

PMID: 24626288

Similar Datasets

Project description:Algal photo-bio hydrogen production, a promising method for producing clean and renewable fuel in the form of hydrogen gas, has been studied extensively over the last few decades. In this study, microarray analyses were used to obtain a global expression profile of mRNA abundance in the green alga Chlamydomonas reinhardtii at five different time points before the onset and during the course of sulphur depleted hydrogen production. The present work confirms previous findings on the impacts of sulphur deprivation but also provides new insights into photosynthesis, sulphur assimilation and carbon metabolism under sulphur starvation towards hydrogen production. For instance, while a general trend towards repression of transcripts encoding photosynthetic genes was observed, the abundance of Lhcbm9 (encoding a major light harvesting polypeptide) and LhcSR1 (encoding a chlorophyll binding protein) was strongly elevated throughout the experiment, suggesting remodeling of the photosystem II light harvesting complex as well as an important function of Lhcbm9 under sulphur starvation. This study presents the first global transcriptional analysis of C. reinhardtii during hydrogen production using five major time points at Peak Oxygen, Mid Oxygen, Zero Oxygen, Mid Hydrogen and Peak Hydrogen. Keywords: Time course, sulfur deprivation, hydrogen production. Time course microarray analyses were used to analyze the global gene expression in sulfur depleted hydrogen producing C. reinhardtii. When depleted of sulfur, a sealed an illuminated C. reinhardtii culture slowly becomes anaerobic and produces hydrogen gas. Based on the changes in the dissolved O2 level and H2 production rate, the whole course of H2 production from the starting of S deprivation to the end of H2 production can be divided into five phases including an Aerobic Phase (I) in which the dissolved O2 level goes up (I), an O2 Consumption Phase (II), an Anaerobic Phase (III), a H2 Production Phase (IV) and a Termination phase (V). Samples were taken from three different bioreactors (biological replicates) at the following time points after the start of S depletion: 6 h, 16 h, 21 h, 37 h and 52 h corresponding to Peak O2, Mid O2, Zero O2, Mid H2 and Peak H2.

Dataset Information

Bioinformatics analysis of alternative polyadenylation in green alga Chlamydomonas reinhardtii using transcriptome sequences from three different sequencing platforms.

Publications

Bioinformatics analysis of alternative polyadenylation in green alga Chlamydomonas reinhardtii using transcriptome sequences from three different sequencing platforms.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets