Tokyo Institute of Technology

About: Tokyo Institute of Technology is a education organization based out in Tokyo, Tôkyô, Japan. It is known for research contribution in the topics: Catalysis & Thin film. The organization has 46775 authors who have published 101656 publications receiving 2357893 citations. The organization is also known as: Tokyo Tech & Tokodai.

Does higher surface temperature intensify extreme precipitation

Abstract: [1] Recently, against the backdrop of current climate, several regional studies have investigated the applicability of the Clausius–Clapeyron relation to the scaling relationship between extreme precipitation intensity and surface air temperature. Nevertheless, the temperature relationship of the extreme precipitation intensity on a global scale is still unclear. We assess, for the first time, the global relationship between the extreme daily precipitation intensity and the daily surface air temperature using in-situ data. The extreme daily precipitation intensity increased monotonically with the daily surface air temperature at high latitudes and decreased monotonically in the tropics. Similarly, the extreme daily precipitation intensity at middle latitudes increased at low temperatures and decreased at high temperatures; this decrease could be largely attributed to the decrease in the wet-event duration. The Clausius–Clapeyron scaling is applicable to the increase in the extreme daily precipitation intensity in a limited number of regions. However, the potential applicability of the Clausius–Clapeyron scaling on sub-hourly timescale was observed, even in regions where the Clausius–Clapeyron scaling on daily timescale was not applicable. This implies the potential of warming to intensify extreme precipitation on sub-hourly timescales.

NELF and DSIF cause promoter proximal pausing on the hsp70 promoter in Drosophila

Abstract: NELF and DSIF collaborate to inhibit elongation by RNA polymerase IIa in extracts from human cells. A multifaceted approach was taken to investigate the potential role of these factors in promoter proximal pausing on the hsp70 gene in Drosophila. Immunodepletion of DSIF from a Drosophila nuclear extract reduced the level of polymerase that paused in the promoter proximal region of hsp70. Depletion of one NELF subunit in salivary glands using RNA interference also reduced the level of paused polymerase. In vivo protein-DNA cross-linking showed that NELF and DSIF associate with the promoter region before heat shock. Immunofluorescence analysis of polytene chromosomes corroborated the cross-linking result and showed that NELF, DSIF, and RNA polymerase IIa colocalize at the hsp70 genes, small heat shock genes, and many other chromosomal locations. Finally, following heat shock induction, DSIF and polymerase but not NELF were strongly recruited to chromosomal puffs harboring the hsp70 genes. We propose that NELF and DSIF cause polymerase to pause in the promoter proximal region of hsp70. The transcriptional activator, HSF, might cause NELF to dissociate from the elongation complex. DSIF continues to associate with the elongation complex and could serve a positive role in elongation.