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The balance between the bioactive sphingolipid ce-ramide and its phosphorylated derivative has been proposed to modulate the amount of programmed cell death (PCD) in eukaryotes. We characterized the first ceramide kinase (CERK) mutant in any organism. The Arabidop-sis CERK mutant, called accelerated cell death 5, accumulates CERK substrates and shows enhanced disease symptoms during pathogen attack and apoptotic-like cell death dependent on defense signaling late in development. ACD5 protein shows high specificity for ce-ramides in vitro. Strikingly, C2 ceramide induces, whereas its phosphorylated derivative partially blocks, plant PCD, supporting a role for ceramide phosphoryla-tion in modulating cell death in plants. Supplemental material is available at http://www.genesdev.org.

The carboxyl-terminal domain of RNA polymerase U contains a tandemly repeated heptapeptide sequence. Previous work has show that this sequence is phosphorylated at multiple sites by a template-associated protein kinase, in a reaction that is closely associated with the Initiation of RNA synthesis. We have purified this kinase to apparent homogeneity from human (HeLa) cells. (4,5). The CTD is composed of repeats of the heptapeptide (SerPro-Thr-Ser-Pro-Ser-Tyr) (6, 7). Phosphorylation occurs cooperatively at multiple serine and threonine residues and induces a conformational change, as evidenced by altered immunoreactivity and sedimentation rate (8,9). The CTD is essential in yeast, Drosophila, and cultured murine cells (10-13). Mutations in the CTD impair the response of RNAP II to certain transcriptional activator proteins (14)(15)(16) ITo whom reprint requests should be addressed. 11920The publication costs of this article were defrayed in part by page charge payment. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. §1734 solely to indicate this fact.

BackgroundAlthough the overall life expectancy at birth has increased for both blacks and whites and the gap between these populations has narrowed, disparities in life expectancy and the leading causes of death for blacks compared with whites in the United States remain substantial. Understanding how factors that influence these disparities vary across the life span might enhance the targeting of appropriate interventions.MethodsTrends during 1999–2015 in mortality rates for the leading causes of death were examined by black and white race and age group. Multiple 2014 and 2015 national data sources were analyzed to compare blacks with whites in selected age groups by sociodemographic characteristics, self-reported health behaviors, health-related quality of life indicators, use of health services, and chronic conditions.ResultsDuring 1999–2015, age-adjusted death rates decreased significantly in both populations, with rates declining more sharply among blacks for most leading causes of death. Thus, the disparity gap in all-cause mortality rates narrowed from 33% in 1999 to 16% in 2015. However, during 2015, blacks still had higher death rates than whites for all-cause mortality in all groups aged <65 years. Compared with whites, blacks in age groups <65 years had higher levels of some self-reported risk factors and chronic diseases and mortality from cardiovascular diseases and cancer, diseases that are most common among persons aged ≥65 years.Conclusions and Implications for Public Health PracticeTo continue to reduce the gap in health disparities, these findings suggest an ongoing need for universal and targeted interventions that address the leading causes of deaths among blacks (especially cardiovascular disease and cancer and their risk factors) across the life span and create equal opportunities for health.

Phosphorylation of the carboxy-terminal domain of the largest subunit of RNA polymerase II is believed to control the transition from transcription initiation to elongation. The general transcription factor IIH (TFIIH) contains a kinase activity capable of phosphorylating this domain. Factors that promote the association of RNA polymerase II with the preinitiation complex stimulate this activity. The transcription factor IIE, which is required for the stable association of TFIIH with the preinitiation complex, affects the processivity of TFIIH kinase.