Alternative splicing of barley clock genes in response to low temperature:evidence for alternative splicing conservation

Alternative splicing (AS) is a regulated mechanism that generates multiple transcripts from individual genes. It is widespread in eukaryotic genomes and provides an effective way to control gene expression. At low temperatures, AS regulates Arabidopsis clock genes through dynamic changes in the levels of productive mRNAs. We examined AS in barley clock genes to assess whether temperature-dependent AS responses also occur in a monocotyledonous crop species. We identify changes in AS of various barley core clock genes including the barley orthologues of Arabidopsis AtLHY and AtPRR7 which showed the most pronounced AS changes in response to low temperature. The AS events modulate the levels of functional and translatable mRNAs, and potentially protein levels, upon transition to cold. There is some conservation of AS events and/or splicing behaviour of clock genes between Arabidopsis and barley. In addition, novel temperature-dependent AS of the core clock gene HvPPD-H1 (a major determinant of photoperiod response and AtPRR7 orthologue) is conserved in monocots. HvPPD-H1 showed a rapid, temperature-sensitive isoform switch which resulted in changes in abundance of AS variants encoding different protein isoforms. This novel layer of low temperature control of clock gene expression, observed in two very different species, will help our understanding of plant adaptation to different environments and ultimately offer a new range of targets for plant improvement

Identification of five bryozoan species in the Northern Mallee Pipeline, Australia

Five species of freshwater bryozoans were identified in the Northern Mallee Pipeline (NMP) system in Victoria, Australia, from statoblast morphology using scanning electron microscopy. The five species were Plumatella emarginata, Fredericella australiensis, Plumatella reticulata, Rumarcanella minuta and Fredericella sultana. The latter three of these have never previously been reported as occurring on the Australian continent and samples have been preserved for safekeeping at Victoria University. The statoblasts were isolated from samples collected as intact colonies from filters and membranes at a number of different locations