We demonstrate correlative super-resolution PALM, PAINT and dSTORM imaging of RNA polymerase, membrane and chromosomal DNA in fixed E. coli. This protocol allows the combination of precise structural information of the nucleoid (dSTORM) with quantitative super-resolution imaging (PALM) of interacting proteins. The spatial distribution and organization of RNA polymerase and DNA are visualized in...

The genome of Vibrio cholerae, the causative agent of cholera, is divided between two circular replicons. Genomic analysis has revealed that several other bacterial species have more than one chromosome. However, to date, the dynamics of chromosome replication in bacteria with more than one chromosome have not been investigated. As in V. cholerae chromosome II (1.07 Mb) is smaller than chromoso...

Meiosis is a specialised type of cell division in sexually reproducing organisms that generates genetic diversity and prevents chromosome doubling in successive generations. The last decade has seen forward and reverse genetic approaches identifying many genes in the plant kingdom which highlight similarities and differences in the mechanics of meiosis between taxonomic kingdoms. We present her...

Platycladus orientalis (L.) Franco (syn. Thuja orientalis L.), Thuja occidentalis L., and T. plicata D. Don. are conifers often used in the landscape. Most of the available cultivars of these species share the character of having foliage that turns an off-color during winter as a result of photoinhibition. Tetraploids of the related japanese-cedar [Cryptomeria japonica (L. f.) D. Don.] have exh...

PREMISE OF THE STUDY Caricaceae include six genera and 34 species, among them papaya, a model species in plant sex chromosome research. The family was held to have a conserved karyotype with 2n = 18 chromosomes, an assumption based on few counts. We examined the karyotypes and genome size of species from all genera to test for possible cytogenetic variation. METHODS We used fluorescent in sit...

MUTATIONS are changes to hereditary material (DNA or RNA) that arise either by an error in replication, or an error in a repair process. In molecular evolution (and population genetics) we are interested in the mechanisms of mutation as it is the ultimate source of novel genetic variation. The scale of the change in DNA or RNA is hugely variable, it can be at an individual nucleotide, at the le...

EIOSIS is a highly integrated system characterized by the orderly procession of events such as pairing, recombination, chiasma formation, and disjunction, which culminates in a reduction o€ chromosome number in the gametes. That this system is under genic control has long been evident from the many mutant genes reported in plants and animals which affect specific stages of the meiotic system. T...