Skip to Main Content

Joan Steitz, PhD

Sterling Professor of Molecular Biophysics and Biochemistry
DownloadHi-Res Photo

Contact Info

Molecular Biophysics and Biochemistry

Department of Molecular Biophysics and Biochemistry, PO Box 9812

New Haven, CT 06519-9812

United States

About

Titles

Sterling Professor of Molecular Biophysics and Biochemistry

Biography

As a college student in the 1960s, Joan Steitz never imagined herself as a top-flight scientist. Certainly, she was fascinated by science. She even assisted senior scientists in laboratories at the Massachusetts Institute of Technology, where she was befriended by James D. Watson, co-discoverer of the DNA double helix, and at the Max Planck Institute in Germany. But when it came time to choose a career path, she had never seen a female professor or head of lab. So, she never aspired to such goals.

Today, Prof. Joan Steitz is one of leading scientists in her field. Steitz is best known for her pioneering work in RNA. She and her student Michael Lerner discovered and defined the function of small ribonucleoproteins (snRNPs) in pre-messenger RNA—the earliest product of DNA transcription—and was the first to learn that these cellular complexes (snRNPs) play a key role in processing messenger RNA by excising noncoding regions and splicing together the resulting segments. Her breakthroughs into the previously mysterious splicing process have clarified the science behind the formation of proteins and other biological processes, including the intricate changes that occur as the immune system and brain develop. Steitz earned her Ph.D. from Harvard in 1967. After completing postdoctoral work in Cambridge, England, she joined the Department of Molecular Biophysics and Biochemistry at Yale as an assistant professor and later became an associate and full professor, as well as chair of the department.

Appointments

Education & Training

PhD
Harvard University (1967)
BS
Antioch College (1963)
Postdoctoral Fellow
Medical Research Council Laboratory of Molecular Biology, Cambridge, England

Research

Overview

RNA-Protein Complexes: Roles in Gene Expression

Noncoding RNAs are important for every step of gene expression. We concentrate on nuclear noncoding RNAs complexed with proteins, where the most famous small nuclear RNPs (snRNPs) participate in pre-mRNA splicing. Current efforts are aimed at understanding how splicing influences downstream events in gene expression via the exon junction complex (EJC), how microRNA biogenesis is regulated during the nuclear maturation steps, and what is the mechanism and function of readthrough transcripts that arise from ~10% of human genes when cells are exposed to stress (osmotic, heat shock or oxidative). Some primate herpesviruses [Epstein-Barr virus (EBV), Herpesvirus saimiri (HVS), and Kaposi sarcoma virus (KSHV)] produce noncoding RNAs that associate with host cell proteins to form snRNPs. Recent investigations have uncovered an unexpected function for an abundant EBV snRNP in the production of viral particles – which is essential for oncogenesis. Other studies have revealed that the HSURs of HVS serve to upregulate genes that are hallmarks of T-cell activation in latently infected T cells — in part by binding and accelerating decay of a particular host microRNA. We have also characterized an RNA element in the PAN RNA of KSHV that counteracts a rapid nuclear RNA decay pathway and solved its high resolution structure, revealing its mechanism of action. Recently, we have discovered new modes of interaction of the polyA with upstream sequences in RNA molecules, most notably a 3'-end binding pocket, all composed completely of RNA.

Medical Subject Headings (MeSH)

Autoantibodies; Biochemistry; Biophysics; Cell Transformation, Viral; Gene Expression; Ribonucleoproteins, Small Nuclear; RNA Processing, Post-Transcriptional

Research at a Glance

Yale Co-Authors

Frequent collaborators of Joan Steitz's published research.

Publications

2022

2021

2019

Academic Achievements & Community Involvement

  • activity

    Proceedings of the National Academy of Sciences

  • honor

    Warren Alpert Prize

  • honor

    Medal Prize Lecture

  • honor

    Watson Prize

  • honor

    D.Sc (Hon)

Get In Touch

Contacts

Academic Office Number
Office Fax Number
Mailing Address

Molecular Biophysics and Biochemistry

Department of Molecular Biophysics and Biochemistry, PO Box 9812

New Haven, CT 06519-9812

United States