Known inducers of the phage shock protein (Psp) system suggest that it is an extracytoplasmic stress response, as are the well-studied RpoE and Cpx systems. However, a random approach to identify conditions and proteins that induce the Psp system has not been attempted. It is also unknown whether the proteins or mutations that induce Psp are specific or if they also activate the RpoE and Cpx sy...

Chloroplast genomes encode rRNAs, tRNAs, and proteins involved in transcription, translation, and photosynthesis. The expression of 15 plastid genes representing each of these functions was quantitated during chloroplast development in barley (Hordeum vulgare). The transcription of all plastid genes increased during the initial phase of chloroplast development and then declined during chloropla...

The phylogenetic structure of ferns (= monilophytes) is explored here, with a special focus on the early divergences among leptosporangiate lineages. Despite considerable progress in our understanding of fern relationships, a rigorous and comprehensive analysis of the early leptosporangiate divergences was lacking. Therefore, a data set was designed here to include critical taxa that were not i...

Maximum likelihood analyses of DNA sequences from two chloroplast regions, trnL-trnF and atpB-rbcL, and the internal transcribed spacers of 18S-5.8S-26S rRNA gene array, were performed to resolve species relationships within the moss genus Hygroamblystegium. Constraining morphospecies to monophyly resulted in significantly less likely trees for H. tenax, but not for the other species. The lack ...

PREMISE OF THE STUDY One third of the species-rich Philippine flora is endemic, and most of the islands in the archipelago have never been connected to a continental region. We currently lack any well-sampled angiosperm phylogenies that span the archipelago, prohibiting the formation of informed hypotheses as to the evolution of this rich and highly endemic flora. METHODS We produced time-cal...

The effect of natural catastrophic events, such as volcanic eruptions and earthquakes, on the genetic structure of species has been infrequently studied. The 1999 Chi-Chi Earthquake of Taiwan resulted in population extinction of Lithocarpus konishii (Fagaceae), an endangered species, and provides a case study for assessing impacts of natural catastrophes on genetic diversity. Genetic diversity ...

Eight optochin-susceptible (Opt(s)) alpha-hemolytic (viridans) streptococcus isolates were characterized at the molecular level. These isolates showed phenotypic characteristics typical of both viridans streptococci and Streptococcus pneumoniae. Comparison of the sequence of housekeeping genes from these isolates with those of S. pneumoniae, Streptococcus mitis, Streptococcus oralis, and Strept...

Rate of substitution of genomic regions is among the most debated intrinsic features that impact phylogenetic informativeness. However, this variable is also coupled with rates of nonsynonymous substitutions that underscore the nature and degree of selection on the selected genes. To empirically address these variables, we constructed four completely overlapping data sets of plastid matK, atpB,...

We have used the Escherichia coli beta-glucuronidase (uidA) gene as a reporter gene to localize the promoter and analyze the function of the 5' untranslated region (UTR) of the Chlamydomonas chloroplast petD gene. Using particle bombardment, petD-uidA transcriptional and translational fusion genes were introduced into the chloroplast genome in the large inverted repeat flanking the atpB gene. I...

APETALA3 (AP3)/DEFICIENS (DEF) is a MADS-box transcription factor that is involved in establishing the identity of petal and stamen floral organs. The AP3/DEF gene lineage has been extensively examined throughout the angiosperms in order to better understand its role in floral diversity and evolution. As a result, a large number of cloned AP3/DEF orthologues are available, which can be used for...