Complete sequences of the plastic1 gene mcrtK \+-eredetermined for 62 species of Poaceae from 6 0 genera. 2 6 tribes. and nine iul~fanliliesto infer phylogenetic relatiollsllips. Rrsfio tetr-upli~llus(Restionaceae) ant1 .loinl illea ascendens (Joi~l\illeacrae) were used as outgroups. Clatlistic. analysis using PAUP)ieltletl 3 9 most parsimo~lioustrees \+-it11several well-supl~orteclmajor lineages. Tlle strict conse~lsusLree she\+-s S~reptocl~cre~a and 4~iomochlocrforming the two most basal lineages in grasses. follo~+-ecl 11) I'licrl-us 11eing sister to the remaining species. The other grasses divide into three clades: (1) sul~fanlil) Banll~~~soitleae (exclucli~lgRrcrchje!,~r7c~ii) plus Pooideae: (2) Oryzoicleae: and (3) s~ll~fanlilies Panicoideae. Ar~lntli~loitleae. monopllyly Cento~hecoideae.ancl Chloridoideae (termed PACC). EacepL for A~~~~~~c l i n o i c l e a e. of each P.1CC subfamily is generally well supported; h o~\ e \ e n relationships among subfamilies are unresolved or weakly supportetl. Results ol~tai~lecl using 117crtK sequences are largely consistent wit11 other phylogenies l~asecl on molecular ancl s~ructural data. particularly in that relationsllips among subfamilies remain ~~n c l e a r. We h a n k Nigel Barker. Lynn Clark. Travis Columbus. Jerr! Davis. Tarciso Filgueiras. Gal? Fleming, Surrey Jac.ol)s. Davicl Kneppet A. Nishiwaki. John Randall, Thomas W'iebolclt, the Botallical Garden at Bo~ill.ant1 the hlissouri Botanical Garden for supplying DNA or plant samples. Seecl material for some accessions was kindl) provided 11) the

Although the matK gene has been used in addressing systematic questions in four families, its potential application to plant systematics above the family level has not been investigated. This paper examines the rates, patterns, and types of nucleotide substitutions in the gene and addresses its utility in constructing phylogenies above the family level. Eleven complete sequences from the GenBank representing seed plants and liverworts and nine partial sequences generated for genera representing the monocot families Poaceae, Joinvilleaceae, Cyperaceae, and Smilacaceae were analyzed. The study underscored the high rate of substitution in the gene and the presence of mutationally conserved sectors. The use of different sectors of the gene and the cumulative inclusion of informative sites showed that the 3' region was most useful in resolving phylogeny, and that the topology and robustness of the tree reached a plateau after the inclusion of 100 informative sites from that region for the taxa used. The impact of using partial sequencing on sample size is addressed. The presence of a relatively conserved 3' region and the less conserved 5' region provides two sets of characters that can be used at different taxonomic levels from the tribal to the division levels.

Mounting evidence suggests that terrestrialization of plants started in streptophyte green algae, favoured by their dual existence in freshwater and subaerial/terrestrial environments. Here, we present the genomes of Mesostigma viride and Chlorokybus atmophyticus, two sister taxa in the earliest-diverging clade of streptophyte algae dwelling in freshwater and subaerial/terrestrial environments, respectively. We provide evidence that the common ancestor of M. viride and C. atmophyticus (and thus of streptophytes) had already developed traits associated with a subaerial/terrestrial environment, such as embryophyte-type photorespiration, canonical plant phytochrome, several phytohormones and transcription factors involved in responses to environmental stresses, and evolution of cellulose synthase and cellulose synthase-like genes characteristic of embryophytes. Both genomes differed markedly in genome size and structure, and in gene family composition, revealing their dynamic nature, presumably in response to adaptations to their contrasting environments. The ancestor of M. viride possibly lost several genomic traits associated with a subaerial/terrestrial environment following transition to a freshwater habitat.

Genome analysis of the pico-eukaryotic marine green alga Prasinoderma coloniale CCMP 1413 unveils the existence of a novel phylum within green plants (Viridiplantae), the Prasinodermophyta, which diverged before the split of Chlorophyta and Streptophyta. Structural features of the genome and gene family comparisons revealed an intermediate position of the P. coloniale genome (25.3 Mb) between the extremely compact, small genomes of picoplanktonic Mamiellophyceae (Chlorophyta) and the larger, more complex genomes of early-diverging streptophyte algae. Reconstruction of the minimal core genome of Viridiplantae allowed identification of an ancestral toolkit of transcription factors and flagellar proteins. Adaptations of P. coloniale to its deep-water, oligotrophic environment involved expansion of light-harvesting proteins, reduction of early light-induced proteins, evolution of a distinct type of C 4 photosynthesis and carbon-concentrating mechanism, synthesis of the metal-complexing metabolite picolinic acid, and vitamin B 1 , B 7 and B 12 auxotrophy. The P. coloniale genome provides first insights into the dawn of green plant evolution.

The 3′ region of the matK gene from 17 species, representing 13 tribes and six subfamilies of the Poaceae, is used to investigate the potential of the gene in addressing systematic questions in the family. The aligned sequences were analyzed by the Wagner parsimony methods using PAUP and PHYLIP and by the neighbor-joining method. Out of the 583 bp sequenced, 30% were variable and 14.9% were informative. The strict consensus tree, rooted by Joinvillea (Joinvilleaceae), showed well-resolved major clades that represent the grass subfamilies. The bambusoid Phyllostachys appeared as a basal clade in the family. Oryza diverged either before or after the Pooideae in the parsimony and neighbor-joining methods, respectively. The three members of the Pooideae grouped in a monophyletic lineage in both analyses. Arundo (Arundinoideae) was basal to the subfamilies Panicoideae and Chloridoideae. Analysis of the various types of DNA mutations underscores the potential of the matK gene in providing insight into grass systematic and evolution. Keywords: matK, Poaceae, grasses, phylogeny, chloroplast, DNA sequence.

Cycads represent one of the most ancient lineages of living seed plants. Identifying genomic features uniquely shared by cycads and other extant seed plants, but not non-seed-producing plants, may shed light on the origin of key innovations, as well as the early diversification of seed plants. Here, we report the 10.5-Gb reference genome of Cycas panzhihuaensis, complemented by the transcriptomes of 339 cycad species. Nuclear and plastid phylogenomic analyses strongly suggest that cycads and Ginkgo form a clade sister to all other living gymnosperms, in contrast to mitochondrial data, which place cycads alone in this position. We found evidence for an ancient whole-genome duplication in the common ancestor of extant gymnosperms. The Cycas genome contains four homologues of the fitD gene family that were likely acquired via horizontal gene transfer from fungi, and these genes confer herbivore resistance in cycads. The male-specific region of the Y chromosome of C. panzhihuaensis contains a MADS-box transcription factor expressed exclusively in male cones that is similar to a system reported in Ginkgo, suggesting that a sex determination mechanism controlled by MADS-box genes may have originated in the common ancestor of cycads and Ginkgo. The C. panzhihuaensis genome provides an important new resource of broad utility for biologists.

Breast cancer is the most commonly diagnosed cancer in females; thus, there is an urgent requirement to identify precise biomarkers for the diagnosis and treatment of the disease. Mucin 1 (MUC1) is a glycoprotein that has been demonstrated to be involved in the metastasis and invasion of multiple tumor types. Bioinformatics analyses were conducted to indicate the prognostic value of MUC1 in breast cancer. Additionally, the expression level of MUC1 was assessed using Oncomine analysis. Furthermore, PrognoScan was used to analyze the prognostic value of MUC1 in breast cancer. Mutations of MUC1 were analyzed by the Catalogue of Somatic Mutations in Cancer and cBioPortal databases. In addition, University of California, Santa Cruz (UCSC) was used to examine the methylation status of MUC1. Co-expression of MUC1 mRNA was detected with the cBioPortal, UCSC and Breast Cancer Gene-Expression Miner v4.0 datasets. The results demonstrated that MCU1 is frequently overexpressed in breast cancer and is negatively associated with CpG sites. Furthermore, pooled data indicated that abnormally high expression of MUC1 indicates poor prognosis. Additionally, upregulation of MUC1 expression is associated with estrogen receptor- and progesterone receptor-positive disease, aging and increased Scarff, Bloom and Richardson grade, but is not associated with triple-negative and basal-like status. Subsequent data mining across multiple large databases demonstrated a positive association between MUC1 mRNA expression and cyclic AMP-responsive element-binding protein 3-like 4 (CREB3L4) in breast cancer tissues. The present data indicated that the overexpression of MUC1 indicates a poor prognosis in patients with breast cancer and is associated with MUC1 promoter methylation status. Additionally, MUC1 positively correlated with CREB3L4 and may serve as a potential prognostic factor and therapy target for breast cancer.

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