Project description:We report the application of RNA-seq technology for highthroughput profiling of photosynthetic and non-photosynthetic seeds of Arabidopsis chlorophyll synthase mutant seeds. By generating over 21 GB of sequence data from these seeds, we showed that genes involved in oil accumulation in non-photosynthetic seeds were significantly induced compared to photosynthtic seeds. Additionally we found that genes involved in the plastidal oxidative pentos phosphate pathway were significantly upregulated in the non-photosynthetic seed opposite to photosynthetic seeds. Overall our RNA-seq analysis revealled the genes and pathway interaction underpinining oil accumulation in non-photosynthetic seeds.
Project description:Ancient oxygenic photosynthetic prokaryotes produced oxygen as a waste product, but existed for a long time under an oxygen-free (anoxic) atmosphere, before an oxic atmosphere emerged. The change in oxygen levels in the atmosphere influenced the chemistry and structure of many enzymes that contained prosthetic groups that were inactivated by oxygen. In the genome of Acaryochloris marina, multiple gene copies exist for proteins that are normally encoded by a single gene copy in other cyanobacteria. Using high throughput RNA sequencing to profile transcriptome responses from cells grown under microoxic and hyperoxic conditions, we detected 8446 transcripts out of the 8462 annotated genes in the Cyanobase database. Two thirds of the 50 most abundant transcripts are key proteins in photosynthesis. Microoxic conditions negatively affected the levels of expression of genes encoding photosynthetic complexes, with the exception of some subunits. In addition to the known regulation of the multiple copies of psbA, we detected a similar transcriptional pattern for psbJ and psbU, which might play a key role in the altered components of photosystem II. Furthermore, regulation of genes encoding proteins important for reactive oxygen species-scavenging is discussed at genome level, including, for the first time, specific small RNAs having possible regulatory roles under varying oxygen levels.
Project description:Antisense RNAs (asRNAs) have diverse functions across three superkingdoms of life. However, their physiological roles for photosynthesis, the most efficient conversion system of solar energy and carbon dioxide into desirable biofuel, are elusive. To understand asRNA-mediated photosynthetic response, we systematically identified non-coding asRNAs and analyzed their differential regulation upon high light and/or low temperature. We found that large fractions of antisense regions are pervasively transcribed and differentially induced upon the change of light and/or temperature. Particularly, photosynthesis and ribosome related genes are mostly regulated by asRNA. Futhermore, we found that 93 long non-coding asRNAs spanning more than half of the cognate open reading frames (ORFs), unexpectedly. Intriguingly, many of them are associated with photosynthetic genes and they have positive role to the expression level of their cognate ORFs. Thus, our systematic transcriptome analysis of photosynthetic response indicates that asRNAs may finetune transcriptional response to enable efficient photosynthetic energy conversion.