The yeast prefoldin-like URI-orthologue Bud27 associates with the RSC nucleosome remodeler and modulates transcription

Bud27, the yeast orthologue of human URI/RMP, is a member of the prefoldin-like family of ATPindependent molecular chaperones. It has recently been shown to mediate the assembly of the three RNA polymerases in an Rpb5-dependent manner. In this work, we present evidence of Bud27 modulating RNA pol II transcription elongation. We show that Bud27 associates with RNA pol II phosphorylated forms (CTD-Ser5P and CTD-Ser2P), and that its absence affects RNA pol II occupancy of transcribed genes. We also reveal that Bud27 associatesin vivo with the Sth1 component of the chromatin remodeling complex RSC and mediates its association with RNA pol II. Our data suggest that Bud27, in addition of contributing to Rpb5 folding within the RNA polymerases, also participates in the correct assembly of other chromatin-associated protein complexes, such as RSC, thereby modulating their activit

Xrn1 influence on gene transcription results from the combination of general effects on elongating RNA pol II and gene-specific chromatin configuration

mRNA homoeostasis is favoured by crosstalk between transcription and degradation machineries. Both the Ccr4-Not and the Xrn1-decaysome complexes have been described to influence transcription. While Ccr4-Not has been shown to directly stimulate transcription elongation, the information available on how Xrn1 influences transcription is scarce and contradictory. In this study we have addressed this issue by mapping RNA polymerase II (RNA pol II) at high resolution, using CRAC and BioGRO-seq techniques in Saccharomyces cerevisiae. We found significant effects of Xrn1 perturbation on RNA pol II profiles across the genome. RNA pol II profiles at 5ʹ exhibited significant alterations that were compatible with decreased elongation rates in the absence of Xrn1. Nucleosome mapping detected altered chromatin configuration in the gene bodies. We also detected accumulation of RNA pol II shortly upstream of polyadenylation sites by CRAC, although not by BioGRO-seq, suggesting higher frequency of backtracking before pre-mRNA cleavage. This phenomenon was particularly linked to genes with poorly positioned nucleosomes at this position. Accumulation of RNA pol II at 3ʹ was also detected in other mRNA decay mutants. According to these and other pieces of evidence, Xrn1 seems to influence transcription elongation at least in two ways: by directly favouring elongation rates and by a more general mechanism that connects mRNA decay to late elongation.Ministerio de Economía y Competitividad BFU2016-77728- C3-1-P, BFU2016-77728-C3-3-P, BFU2016- 77728-C3-2-P, RED2018-102467-TJunta de Andalucía BIO271, US-1256285, BIO258, UJA 1260360Generalitat Valenciana AICO/2019/08

Phytosociological characteristic of Latvian beaches and dunes within the context of the Baltic Sea region

Anotācija Laime B. 2010. Latvijas kāpu un pludmaļu fitosocioloģiskais raksturojums Baltijas jūras reģiona kontekstā Pētījumā raksturota piekrastes veģetācija 5998 parauglaukumos. Izmantojot TWINSPAN, DCA metodi un JUICE programmu, izstrādāta Latvijas piekrastes veģetācijas sintaksonomiskā klasifikācija, kas ietver 5 klases un 9 asociācijas: Juncetum bufonii, Atriplicetum littoralis, Cakiletum maritimae, Honckenyetum peploidis, Elymo-Ammophiletum arenariae, Festucetum polesicae, Caricetum arenariae, Corniculario aculatae-Corynephoretum canescentis un Carici-Callunetum. Raksturota katras asociācijas veģetācija, ekoloģija, izplatība un aizsardzība. Nodalīti vairāki sukcesiju tipi. Iegūtie rezultāti salīdzināti ar līdzīgiem pētījumiem Baltijas jūras reģionā. Atslēgvārdi: veģetācija, augu sabiedrība, Ammophiletea, Cakiletea, Koelerio-CorynephoreteaAnnotation Laime B. 2010. Phytosociological characteristic of Latvian beaches and dunes within the context of the Baltic Sea region Vegetation in 5998 sample plots was described. Using TWINSPAN, DCA method and program JUICE, the syntaxonomical classification of Latvian coastal vegetation was carried out, distinguished 5 classes, 9 associations: Juncetum bufonii, Atriplicetum littoralis, Cakiletum maritimae, Honckenyetum peploidis, Elymo-Ammophiletum arenariae, Festucetum polesicae, Caricetum arenariae, Corniculario aculatae-Corynephoretum canescentis and Carici-Callunetum. Vegetation, ecology, distribution and protection of each syntaxon, and several types of succession were characterised. Results are compared with similar communities in the Baltic Sea region. Key words: vegetation, plant communities, Ammophiletea, Cakiletea, Koelerio-Corynephorete

Iwr1 nuclear localization is independent of Bud27.

<p>Live cell imaging of Iwr1-Gfp deleted for its NES domain in wild-type and Δ<i>bud27</i> cells at 30°C.</p

Bud27 physically interacts with the three RNA polymerases.

<p>A) Growth of BUD27-TAP, Wild-type and a Δ<i>bud27</i> cells inYPD at the indicated temperatures. B) Summary of the proteins interacting with Bud27 in a TAP purification analysis. C) Western blot of protein co-purified with Bud27-TAP (3), Rpb3-TAP (2), and non- tagged wild-type strains (1). anti-HA, anti-Myc, anti-Rpb1 (8WG16), and anti-PAP antibodies were used. No tag: wild-type strain BY4741; Rpb3-TAP: Rpb3-TAP, Rpa190-HA (RNA pol I) and Rpc25-Myc (RNA pol III) strain; Bud27-TAP: Bud27-TAP, Rpa190-HA (RNA pol I) and Rpc25-Myc (RNA pol III) strain.</p

RNA pol I, II, and III nuclear localization is independent of the chaperone prefoldin (PFD) complex.

<p>Live cell imaging of Rpb8-ECFP and Rpb1-GFP in Δ<i>bud27</i>, Δ<i>gim6</i> (Δ<i>pfd1</i>), Δ<i>gim4</i> (Δ<i>pfd2</i>), and Δ<i>yke2</i> (Δ<i>pfd6</i>) mutant cells containing C-terminal ECFP tagged Rpb8 and C-terminal GFP tagged Rpb1, at 30°C.</p

PFD, Rpb5-binding domains, or both are dispensable for RNA pol I, II, and III nuclear localization.

<p>Live cell imaging of Rpb8-ECFP and Rpb1-GFP in Δ<i>bud27</i> mutant cells at 30°C, containing vectors overexpressing whole <i>BUD27</i> or <i>BUD27</i> deleted for PFD, Rpb5-binding domains or both.</p