108 research outputs found
New approaches towards sustainability of land-use systems in Tropical Brazil.
The SHIFT-Program ENV 44 tries to maintain soil fertility in the Bragantina area (Pará) by production of mulch material from fallow vegetation. A main focus with respect to sustainability deserves to be agroforestry
Persistência de endossulfam e seu metabólito sulfato de endossulfam em condições de campo e laboratório
FACT Prevents the Accumulation of Free Histones Evicted from Transcribed Chromatin and a Subsequent Cell Cycle Delay in G1
The FACT complex participates in chromatin assembly and disassembly during transcription elongation. The yeast mutants affected in the SPT16 gene, which encodes one of the FACT subunits, alter the expression of G1 cyclins and exhibit defects in the G1/S transition. Here we show that the dysfunction of chromatin reassembly factors, like FACT or Spt6, down-regulates the expression of the gene encoding the cyclin that modulates the G1 length (CLN3) in START by specifically triggering the repression of its promoter. The G1 delay undergone by spt16 mutants is not mediated by the DNA–damage checkpoint, although the mutation of RAD53, which is otherwise involved in histone degradation, enhances the cell-cycle defects of spt16-197. We reveal how FACT dysfunction triggers an accumulation of free histones evicted from transcribed chromatin. This accumulation is enhanced in a rad53 background and leads to a delay in G1. Consistently, we show that the overexpression of histones in wild-type cells down-regulates CLN3 in START and causes a delay in G1. Our work shows that chromatin reassembly factors are essential players in controlling the free histones potentially released from transcribed chromatin and describes a new cell cycle phenomenon that allows cells to respond to excess histones before starting DNA replication
Daughter-Specific Transcription Factors Regulate Cell Size Control in Budding Yeast
The asymmetric localization of cell fate determinants results in asymmetric cell cycle control in budding yeast
Persistência e lixiviação de ametryn e trifloxysulfuron-sodium em solo cultivado com cana-de-açúcar
Emprego do carvão ativado para remoção de atrazina em água de abastecimento público
Remoção de atrazina e metabólitos pela filtração lenta com leito de areia e carvão ativado granular
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