Coordinating Transcription and Translation in Eukaryotes
Event details
| Date | 17.08.2015 |
| Hour | 12:15 |
| Speaker | Prof. Brian M. Zid, UC San Diego, La Jolla, CA (USA) |
| Location | |
| Category | Conferences - Seminars |
BIOENGINEERING SEMINAR
(sandwiches served)
Abstract:
In eukaryotes, transcription and translation are considered to be discrete processes both spatially and in terms of regulatory factors. On the other hand, close coordination of transcription and translation for subsets of cellular mRNAs would be advantageous when an organism needs to rapidly alter its cellular composition, such as during environmental stress. A universal feature of the response to stress and nutrient limitation is transcriptional upregulation of genes encoding proteins important for survival. Under many of these conditions overall protein synthesis levels are reduced, thereby dampening the stress response at the level of protein expression. For example, during glucose starvation in yeast, translation is rapidly repressed, yet transcription of many stress- and glucose-repressed genes is increased. Using ribosome profiling and microscopy, we found that this transcriptionally upregulated gene set consists of two classes: (1) one producing mRNAs that are translated during glucose limitation and are diffusely localized in the cytoplasm – this class includes many heat shock protein mRNAs; and (2) another producing mRNAs that are not efficiently translated during glucose limitation and are concentrated in foci that co-localize with P bodies and stress granules – this class is enriched for glucose metabolism mRNAs. Surprisingly, the information specifying differential localization and protein production of these two classes of mRNAs is encoded in the promoter sequence – promoter responsiveness to heat shock factor (Hsf1) specifies diffuse cytoplasmic localization and higher protein production upon glucose starvation. Thus, promoter sequences and transcription factor binding can influence not only mRNA levels, but also subcellular localization of mRNAs and the efficiency with which they are translated, enabling cells to tailor protein production to environmental conditions.
Bio:
Education:
California Institute of Technology, Pasadena CA, Ph.D., 2008, Biology
Truman State University, Kirksville MO, B.S., 2000, Chemistry
Research Experience:
Assistant Professor of Biochemistry – UC San Diego July 2015 – present
Postdoctoral Fellow in the lab of Erin O’Shea, Harvard University, Nov 2008 – June 2015
Graduate Student in the lab of Seymour Benzer, California Institute of Technology, Jan 2001–Oct 2008
(sandwiches served)
Abstract:
In eukaryotes, transcription and translation are considered to be discrete processes both spatially and in terms of regulatory factors. On the other hand, close coordination of transcription and translation for subsets of cellular mRNAs would be advantageous when an organism needs to rapidly alter its cellular composition, such as during environmental stress. A universal feature of the response to stress and nutrient limitation is transcriptional upregulation of genes encoding proteins important for survival. Under many of these conditions overall protein synthesis levels are reduced, thereby dampening the stress response at the level of protein expression. For example, during glucose starvation in yeast, translation is rapidly repressed, yet transcription of many stress- and glucose-repressed genes is increased. Using ribosome profiling and microscopy, we found that this transcriptionally upregulated gene set consists of two classes: (1) one producing mRNAs that are translated during glucose limitation and are diffusely localized in the cytoplasm – this class includes many heat shock protein mRNAs; and (2) another producing mRNAs that are not efficiently translated during glucose limitation and are concentrated in foci that co-localize with P bodies and stress granules – this class is enriched for glucose metabolism mRNAs. Surprisingly, the information specifying differential localization and protein production of these two classes of mRNAs is encoded in the promoter sequence – promoter responsiveness to heat shock factor (Hsf1) specifies diffuse cytoplasmic localization and higher protein production upon glucose starvation. Thus, promoter sequences and transcription factor binding can influence not only mRNA levels, but also subcellular localization of mRNAs and the efficiency with which they are translated, enabling cells to tailor protein production to environmental conditions.
Bio:
Education:
California Institute of Technology, Pasadena CA, Ph.D., 2008, Biology
Truman State University, Kirksville MO, B.S., 2000, Chemistry
Research Experience:
Assistant Professor of Biochemistry – UC San Diego July 2015 – present
Postdoctoral Fellow in the lab of Erin O’Shea, Harvard University, Nov 2008 – June 2015
Graduate Student in the lab of Seymour Benzer, California Institute of Technology, Jan 2001–Oct 2008
Practical information
- Informed public
- Free