Genes for the plastid-encoded RNA polymerase (PEP) persist in the plastid genomes of all photosynthetic angiosperms. However, three unrelated lineages (Annonaceae, Passifloraceae and Geraniaceae) have been identified with unusually divergent open reading frames (ORFs) in the conserved region of rpoA, the gene encoding the PEP α subunit. We used sequence-based approaches to evaluate whether thes...

Angiosperm systematics has progressed to the point where it is now expected that multiple, independent markers be used in phylogenetic studies. Universal primers for amplifying informative regions of the chloroplast genome are readily available, but in the faster-evolving nuclear genome it is challenging to discover priming sites that are conserved across distantly related taxa. With goals incl...

Although gene coevolution has been widely observed within individuals and between different organisms, rarely has this phenomenon been investigated within a phylogenetic framework. The Geraniaceae is an attractive system in which to study plastid-nuclear genome coevolution due to the highly elevated evolutionary rates in plastid genomes. In plants, the plastid-encoded RNA polymerase (PEP) is a ...

The study of the chemical constituents of the whole plant of Geranium wallichianum (Geraniaceae) has resulted in the isolation and characterization of six compounds. These six compounds were identified as ursolic acid (1), β-sitosterol (2), stigmasterol (3), β-sitosterol galactoside (4), herniarin (5), and 2,4,6-trihydroxyethylbenzoate (6) which were isolated for the first time from Geranium wa...

The filaree (Erodium cicutarium), a small, flowering plant related to geraniums, possesses a unique seed dispersal mechanism: the plant can fling its seeds up to half a meter away; and the seeds can bury themselves by drilling into the ground, twisting and untwisting in response to changes in humidity. These feats are accomplished using awns, helical bristles of dead but hygroscopically active ...