The flowering of Arabidopsis thaliana winter annuals is delayed until the subsequent spring by the strong floral repressor FLOWERING LOCUS C (FLC). FRIGIDA (FRI) activates the transcription of FLC, but the molecular mechanism remains elusive. The fri mutation causes early flowering with reduced FLC expression similar to frl1, fes1, suf4, and flx, which are mutants of FLC-specific regulators. He...

The detection of footprints of natural selection in genetic polymorphism data is fundamental to understanding the genetic basis of adaptation, and has important implications for human health. The standard approach has been to reject neutrality in favor of selection if the pattern of variation at a candidate locus was significantly different from the predictions of the standard neutral model. Th...

In the winter-annual accessions of Arabidopsis thaliana, presence of an active allele of FRIGIDA (FRI) elevates expression of FLOWERING LOCUS C (FLC), a repressor of flowering, and thus confers a vernalization requirement. FLC activation by FRI involves methylation of Lys 4 of histone H3 (H3K4) at FLC chromatin. Many multicellular organisms that have been examined contain two classes of H3K4 me...

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We traced diatom composition and diversity through time using diatom-derived sedimentary ancient DNA (sedaDNA) from eastern continental slope sediments off Kamchatka (North Pacific) by applying a short, diatom-specific marker on 63 samples in metabarcoding approach. The sequences were assigned to diatoms that are common the area characteristic of cold water. SedaDNA allowed us observe shifts po...

This work summarizes ice algal studies, presented as biomass and species temporal spatial distribution, during 11 cruises conducted between 1986 2012. The majority of the was found loosely attached sub-ice layers, sampling required diving. A maximum 40 mg chlorophyll m−2 15.4 × 109 cells measured in May. diversity separated zones based on thickness, with highest biodiversity medium-thick 30–80 ...

FRIGIDA (FRI) is a major gene involved in the regulation of flowering time in Arabidopsis thaliana. Nucleotide variation at this gene was investigated by sequencing 25 field ecotypes collected from western Europe. Genetic diversity at FRI was characterized by a high number of haplotypes and an excess of low-frequency polymorphisms. A large excess of intraspecific nonsynonymous variation associa...