Project description:This study aimed at identification of genetic regulations for desiccation tolerance in intertidal seaweed species Ulva lactuca most commonly experienced phenomenon of intertidal communities. Overall design: The algal thalli were collected and acclamatised to laboratory. The experiments were designed for desiccation for different durations at a moisture condition of 20%. The thalli were desiccated for 24 h, 36 h and 72 h and investigated for transcriptomics by RNA-seq. Differential expression of genes determine the genetic regulations for desiccation tolerance in this lower group of aquatic plants. Please note that the current study represents the re-analysis of the GSE97769 samples (GSM2577150, GSM2577148, GSM2577151, GSM2577153) based on a different assembly.
Project description:This study aimed at identification of genetic regulations for desiccation and submergence tolerance in intertidal seaweed species Ulva lactuca which arisies periodically due to tidal rhythms. Overall design: The algal thalli were collected and acclamatised to laboratory. The experiments were designed for desiccation for different durations at a moisture condition of 20%. The thalli were desiccated for 24 h, 36 h and 72 h and investigated for transcriptomics by RNA-seq. After each desiccation time point, the thalli were resubmerged in autoclaved seawater. After 1 h of resubmergence, thalli were collected and processed for RNA extraction and subsequent RNA-seq. The transtion of desiccation to submergence will determine the genetic regulations for submergence tolerance in this group of plants.
Project description:Small RNAs (21-24 nt) are pivotal regulators of gene expression that guide both transcriptional and post-transcriptional silencing mechanisms in diverse eukaryotes, including most if not all plants. MicroRNAs (miRNAs) and short interfering RNAs (siRNAs) are the two major types, both of which have a demonstrated and important role in plant development, stress responses and pathogen resistance. In this work, we used a deep sequencing approach (Sequencing-By-Synthesis, or SBS) to develop sequence resources of small RNAs from different Lactuca sativa tissues (including leaves, flowers, and fungus-infected leaves). The high depth of the resulting datasets enabled us to examine in detail critical small RNA features such as size distribution, tissue-specific regulation and sequence conservation between different organs in this species. We also developed database resources and a dedicated website (http://smallrna.udel.edu/) with computational tools for allowing other users to identify new miRNAs or siRNAs involved in specific regulatory pathways, verify the degree of conservation of these sequences in other plant species and map small RNAs on genes or larger regions of the genome under study. Small RNA libraries were derived from leaves and flowers of Lactuca sativa, cultivar Salinas, including leaves infected with the fungus Bremia lactucae, strain CA-III. Total RNA was isolated using TriReagent® (Molecular Research Center) and submitted to Illumina (Hayward, CA, http://www.illumina.com) for small RNA library construction using approaches described in (Lu et al., 2007) with minor modifications. The small RNA libraries were sequenced with the Sequencing-By-Synthesis (SBS) technology by Illumina. PERL scripts were designed to remove the adapter sequences and determine the abundance of each distinct small RNA. We thank Richard Michelmore and Oswaldo Ochoa for providing the plant material as well as Kan Nobuta for assistance with the computational methods.