Johnson's research focuses on understanding gene regulation, chromatin modification, RNA splicing and how regulating splicing allows cells to respond to their environment.[2] Specifically, her group studies the spliceosome, a macromolecular "machine" made of five subunits that interacts with a pre-messenger RNA to produce an edited version,[3] leading to appropriate translation into proteins. Her group has provided evidence that spliceosome assembly around a nascent mRNA transcript is regulated by histone modifications in the chromatin of the transcribed region.[4][5]
From 2003 to 2013, Johnson was a member of the University of California San Diego biological sciences faculty where she earned many awards, including the National Science Foundation (NSF) Presidential Early Career Award for Scientists and Engineers (PECASE) and the UCSD Chancellor's Associates Award for Excellence in Undergraduate Teaching.[6] Johnson joined the faculty of the University of California, Los Angeles in 2013 as the professor of molecular, cell, and developmental biology and holder of the Keith and Cecilia Terasaki Presidential Endowed Chair.[1] In 2014, she was named a Howard Hughes Medical Institute Professor,[6] and became the associate dean for inclusive excellence in the division of life sciences in 2015.[1] She was named dean of the UCLA Division of Life Sciences in 2020.[1]
Johnson has also focused on developing programs to create transformative learning experiences for undergraduates[7] including the UCLA-HHMI Pathways to Success Program.[8] The program is a comprehensive strategy to provide students with an authentic research experience early in their academic careers.[7] The program has three key components: (1) A research-based laboratory course, (2) a mentoring network that integrates peer and hierarchical mentoring, and (3) intensive learning communities.[7] Johnson is known for her work on diversity, equity and inclusion in STEM, and was awarded the UCLA Academic Senate Award for Career Commitment to Diversity, Equity and Inclusion and the UCLA Life Sciences Award for Inclusive Excellence through teaching, mentorship, service and research.[1]
Honors and awards
Maria Rowena Ross Chair of Cell Biology and Biochemistry[6]
Associate Dean for Inclusive Excellence, UCLA Life Sciences (2015)[1]
Howard Hughes Medical Institute (HHMI) Professor (2014)[8][2]
Chancellor's Associates Award for Excellence in Undergraduate Teaching[6] (2013)
National Science Foundation (NSF) Presidential Early Career Award for Scientists and Engineers (PECASE) (2006)[9]
Publication
Barber, P. H., Hayes, T. B., Johnson, T. L., & Márquez-Magaña, L. (2020). Systemic racism in higher education. Science (American Association for the Advancement of Science), 369(6510), 1440–1441.[10]