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BIO-Annual-Report-2003.Pdf 118393_Caltech_Cover_r1 12/10/03 6:04 AM Page 2 Legend for the front cover illustration Sylvian Bauer and Professor of Biology Paul H. Patterson Apoptosis-committed olfactory sensory neurons, as evidenced in only one side of the nasal septum by strong TUNEL staining present in the olfactory epithelium two days after unilateral axotomy (black and white picture), were shown by in situ RT-PCR to express the cytokine LIF mRNA (right blue picture) as soon as eight hours post-lesion. Mature olfactory sensory neurons were identified on the adjacent section by in situ hybridization for olfactory marker protein (OMP, left blue picture). Legend for the back cover illustration Farshad Moradi and Professor of Biology Christof Koch Human brain activation following visual stimulation by photographs of faces versus scenes and non-face objects. Color map indicates voxels that showed a significant BOLD signal change during exposure (red: faces, blue: scenes. See color key at the middle right side), overlaid on T1-weighted anatomical images (top: axial, middle: sagittal, bottom: coronal slices). The 3 experiment was conducted in the 3.0-Tesla human magnet at Caltech's new Brain Imaging Center (3.3 x 3.3 x 3 mm voxels, Assistant Professor of Biology, Bren Scholar, David C. Chan TR = 2 s, TE = 30 ms). Disruption of mitofusin 1 (Mfn1) in mouse cells results in a severe reduction in mitochondrial fusion. When Mfn1 mutant cells containing GFP (green) or dsRed (red) labeled mitochondria are fused by polythylene glycol (PEG), the mitochondria in fused cells fail to fuse and therefore remain distinctly green or red. Division of Biology California Institute of Technology Pasadena, CA Annual Report 2002 - 2003 BIOLOGY - 2003 Yolanda Duron, Annual Report Coordinator Research Reports Biological research summarized in this report covers the time period from June, 2002, through July, 2003. The annual report is not intended to serve as an official forum, since some portions of the research listed in this report have not yet been published. When referring to an individual abstract(s), special permission must be obtained from the investigator. References to published papers cited throughout the report are listed at the end of each individual research report. TABLE OF CONTENTS INTRODUCTION INSTRUCTION AND RESEARCH STAFF...............................................................13 ADMINISTRATIVE STAFF ..............................................................................22 DEVELOPMENTAL AND REGULATORY BIOLOGY JOSÉ ALBEROLA-ILA, PH.D. Summary.......................................................................................................................................................................... 25 1. Gata-3 expression is regulated by TCR signals and controls CD8 and CD8 T-cell development............................... 25 2. Elucidating the role of the Ras/MAP kinase pathway in lineage determination of thymocytes using a lentiviral transgenesis model ................................................................................................................................ 26 3. Analysis of the role of Ras signaling during T cell development ................................................................................. 26 4. KSR connects Ras to the MAPK cascade ...................................................................................................................... 26 5. EGR transcription factors as mediators of Ras signaling during thymocyte selection................................................. 27 6. Regulation of T-cell development by Notch: Proliferation vs. differentiation............................................................ 27 7. Real-time detection of MAPK activity using fluorescence resonance energy transfer ................................................ 28 8. Role of Phosphatidylinositol 3-kinase plays during T cell development...................................................................... 28 9. Chemical-genetic analysis of the role of Lck in T cell signaling .................................................................................. 29 Publications ..................................................................................................................................................................... 29 MARIANNE BRONNER-FRASER, PH.D. Summary.......................................................................................................................................................................... 30 10. Wnt in the ectoderm functions as a neural crest inducer ............................................................................................... 30 11. Genomic analysis of neural crest induction.................................................................................................................... 30 12. Id gene expression in amphioxus and lamprey highlights the role of genetic co-option during neural crest evolution.......................................................................................................................................................... 31 13. Neural crest contributions to the lamprey head.............................................................................................................. 31 14. Excess FoxG1 causes overgrowth of the neural tube .................................................................................................... 31 15. Dual function of Slit2 in repulsion and enhanced migration of trunk but not vagal neural crest ................................ 31 16. Neuronal differentiation from post-mitotic precursors in the ciliary ganglion............................................................. 32 Publications ..................................................................................................................................................................... 32 ERIC H. DAVIDSON, PH.D. Summary.......................................................................................................................................................................... 33 17. Further analysis of early zygotic regulators in the endomesoderm network................................................................. 35 18. Micromere-PMC GRN.................................................................................................................................................... 36 19. Mapping the functional elements in the Otx endodermal specific modules and the interrelationship of the inputs of Krox, GATA (e) and Otx ................................................................................................................... 36 20. Identify the negative elements regulate the endo16 promoter and developing a useful tool for identified the unknown negative module in the sea urchin genome....................................................................................... 37 21. Transcriptional control of the sea urchin brachyury gene ............................................................................................. 37 22. Notch signaling role in endomesoderm specification in sea urchin.............................................................................. 38 23. Refinement of a cis-regulatory model for cyIIIa............................................................................................................ 38 24. cis-Regulatory analysis of the sea urchin delta gene ..................................................................................................... 38 25. SpKrox1 and the endomesoderm network ..................................................................................................................... 39 26. cis-Regulatory analysis of Spgata-e ............................................................................................................................... 39 27. Snail and Twist and their role in mesoderm specification in sea urchin....................................................................... 39 28. cis-Regulatory analysis of SpWnt8 ................................................................................................................................. 40 29. Expression patterns of various genes that play parts in the gene regulatory network for early development of the sea urchin Strongylocentrotus purpuratus.................................................................................................... 40 30. Functions of SpSoxB1 and SpKrl in sea urchin development....................................................................................... 40 i ERIC H. DAVIDSON, PH.D. 31. Spdeadringer, a sea urchin embryo gene required separately in skeletogenic and oral ectoderm gene regulatory networks ................................................................................................................................................. 41 32. SpCyclophillin: A downstream target of Spdri in the PMC territory .......................................................................... 42 33. Hepatocyte nuclear factor-6: A positively acting regulatory gene of the sea urchin embryo ..................................... 42 34. Purification of the spatial control factors of the sm50 gene and the possible mechanism of DNA-protein and protein-protein interactions at the C-element............................................................................ 42 35. AmHNF-6: New member of the ONECUT class of transcription factor expressed in starfish embryos..................
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