We report the draft genome sequence of the model moss Physcomitrella patens and compare its features with those of flowering plants, from which it is separated by more than 400 million years, and unicellular aquatic algae. This comparison reveals genomic changes concomitant with the evolutionary movement to land, including a general increase in gene family complexity; loss of genes associated with aquatic environments (e.g., flagellar arms); acquisition of genes for tolerating terrestrial stresses (e.g., variation in temperature and water availability); and the development of the auxin and abscisic acid signaling pathways for coordinating multicellular growth and dehydration response. The Physcomitrella genome provides a resource for phylogenetic inferences about gene function and for experimental analysis of plant processes through this plant's unique facility for reverse genetics.

The first chordates appear in the fossil record at the time of the Cambrian explosion, nearly 550 million years ago. The modern ascidian tadpole represents a plausible approximation to these ancestral chordates. To illuminate the origins of chordate and vertebrates, we generated a draft of the protein-coding portion of the genome of the most studied ascidian, Ciona intestinalis. The Ciona genome contains ϳ16,000 protein-coding genes, similar to the number in other invertebrates, but only half that found in vertebrates. Vertebrate gene families are typically found in simplified form in Ciona, suggesting that ascidians contain the basic ancestral complement of genes involved in cell signaling and development. The ascidian genome has also acquired a number of lineage-specific innovations, including a group of genes engaged in cellulose metabolism that are related to those in bacteria and fungi.

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Gene expression after leaf rust infection was compared in near-isogenic wheat lines differing in the Lr10 leaf rust resistance gene. RNA from susceptible and resistant plants was used for cDNA library construction. In total, 55 008 ESTs were sequenced from the two libraries, then combined and assembled into 14 268 unigenes for further analysis. Of these ESTs, 89% encoded proteins similar to (E value of ≤10−5) characterized or annotated proteins from the NCBI non-redundant database representing diverse molecular functions, cellular localization and biological processes based on gene ontology classification. Further, the unigenes were classified into susceptible and resistant classes based on the EST members assembled from the respective libraries. Several genes from the resistant sample (14-3-3 protein, wali5 protein, actin-depolymerization factor and ADP-ribosylation factor) and the susceptible sample (brown plant hopper resistance protein, caffeic acid O-methyltransferase, pathogenesis-related protein and senescence-associated protein) were selected and their differential expression in the resistant and susceptible samples collected at different time points after leaf rust infection was confirmed by RT–PCR analysis. The molecular pathogenicity of leaf rust in wheat was studied and the EST data generated made a foundation for future studies.

About 1 million expressed sequence tag (EST) sequences comprising 125.3 Mb nucleotides were accreted from 51 cDNA libraries constructed from a variety of tissues and organs under a range of conditions, including abiotic stresses and pathogen challenges in common wheat (Triticum aestivum). Expressed sequence tags were assembled with stringent parameters after processing with inbuild scripts, resulting in 37 138 contigs and 215 199 singlets. In the assembled sequences, 10.6% presented no matches with existing sequences in public databases. Functional characterization of wheat unigenes by gene ontology annotation, mining transcription factors, full-length cDNA, and miRNA targeting sites were carried out. A bioinformatics strategy was developed to discover single-nucleotide polymorphisms (SNPs) within our large EST resource and reported the SNPs between and within (homoeologous) cultivars. Digital gene expression was performed to find the tissue-specific gene expression, and correspondence analysis was executed to identify common and specific gene expression by selecting four biotic stress-related libraries. The assembly and associated information cater a framework for future investigation in functional genomics.

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