Dustin Updike

Education

• B.S. University of Wyoming, 1999
• PhD, University of Utah, 2006

Research Interests

Germ cells are the progenitors of reproductive cells, and the only cells in sexually reproducing animals that have the potential to give rise to all of the cell types of each subsequent generation. In our lab, we want to understand how these totipotent and immortal properties are conferred.  Part of the answer comes from special aggregates called “germ granules” that are found just outside the nucleus of germ cells. Recent research has shown that germ granules play a critical role in maintaining the totipotent and immortal properties of the germline. Take away an organism’s germ granules and it will become sterile. In some organisms, introducing germ granules in cells outside of the germline will restore cellular immortality and totipotency, and will reprogram them into germline stem cells.

Germ granules are conserved in their appearance, subcellular localization, and composition from worms to humans.  Because of this, we are able to quickly ascertain the mechanisms by which germ granules function by studying them in a small roundworm called C. elegans.  This well-established model organism is responsible for much of what we know about developmental genetics in humans.  Using fluorescence microscopy, germ granules (called P granules in C. elegans) can be observed in the germ line of transparent worms at all stages of development.  The genetic power of C. elegans combined with its short 3-day generation time and transparency offers an opportunity to study the function of germ granules that isn’t feasible in more complex model organisms.

A focus of our research is to understand the biophysical properties of germ granules, how they are assembled, and the components that affect their subcellular distribution.  We have shown that germ granules are held together by weak hydrophobic interactions, and that they extend the size exclusion barrier of the nuclear pore complex out into the cytoplasm of germ cells.  Here germ granules create a specialized microenvironment that facilitates post-transcriptional processing events that are exclusive to the germline.  We are continuing to investigate the specifics of those processing events to understand how they are used to maintain the pluripotent and immortal properties of germ cells, and how these mechanisms can be applied to unlocking stem cell-like properties in other cell types.

How do stem cells maintain pluripotency — the capacity to become other cell types in the body? Can our ability to regenerate after disease or injury be improved with the ability to switch on and off cellular pluripotency?

To answer these and other questions, the Updike Lab derives cues from quintessential stem cells found in the germline. Germline stem cells (GSCs) are the precursors to oocytes and sperm, and these cells must retain their stem cell attributes so fertilized embryos can give rise to all of the cell types of each subsequent generation.

To achieve this immortal potential, germ cells survey gene expression activity through unique structures called germ granules in the cell’s cytoplasm. Germ granules use small RNA machinery to read cellular messages and determine whether they are licensed for expression, shutting down aberrant messages whose expression could result in the loss of pluripotency. While germ granules are specific to the germline, they are found in animals, from worms to humans. The Updike Lab studies germ-granule function in C. elegans nematodes, where they are readily accessible and visible at all stages of development. This work will impact our understanding of germ-granule function and human fertility and the role of the cell’s cytoplasm in wound healing, regeneration, and tumorigenesis.

Selected Publications

Selected Services

• 2012 to 2015 — GSBSE Admissions Committee
• 2013 to 2015 — MDI Bio Lab Seminar Speakers Committee Chair
• 2014 to 2015 — Intro to Development Foundations Course Lecturer
• 2014 to 2015 — MDI Bio Lab Outreach Instructor – Developmental Genetics using C. elegans
• 2016 to present — MDI Bio Lab Outreach Instructor – Genomic Engineering using CRISPR/Cas9
• 2017 to present — Maine INBRE Program Coordinator

Selected Grants

Dissertation Students

Jesse Rochester