Dr. Gomer’s lab is studying how cells regulate their own proliferation, why some patients have wounds that do not heal, and why some patients form large masses of scar tissue in organs such as the lungs.
- Identify signals that Dictyostelium cells secrete to slow or stop their own proliferation.
- Determine the signal transduction pathways used by these signals to slow or stop proliferation.
- Determine what regulates the differentiation of some white blood cells into scar tissue.
- A secreted proliferation-inhibiting compound also acts as a chemorepellent, leading to a potential therapeutic for neutrophil-driven diseases such as acute respiratory distress syndrome.
Cell Number Counting
What regulates the size of a tissue? A secreted signal can be used to sense the number of cells in a group. If the group is too large, the signal can either stop cell proliferation or, by increasing random motility and/or decreasing adhesion, cause the group to break into smaller groups.Our lab is working to understand how cell number counting works by studying Dicty mutants with defects in their size-determination mechanism. Two of these mutants are smlA, which forms more than the normal number of aggregates and countin, in which the aggregation streams do not break up and huge fruiting bodies form.
Cell Density Sensing
Every organism is made up of different cell types, but how does the system sense the relative proportions of the different cell types? We found that by using secreted signals, cells can sense the composition of a tissue that contains a variety of cell types. When a Dicty cell starves, it signals that it is starving by slowly secreting a cell density sensing factor, the glycoprotein conditioned medium factor (CMF).
Cell-cycle Dependent Initial Cell-type choice
When an embryo starts growing, how do the cells decide what type of cell to become (bone, muscle, nerve, etc)? We found a simple and elegant mechanism that lets a population of cells break symmetry and differentiate into separate cell types.
Exotic Star Binaries
Accretion disks are made of gas orbiting and falling into a central mass. Disks are found around the central massive black hole in a quasars. When a disk forms around a star, it can condense into planets. In collaboration with Dr. Keith Horne of the University of St. Andrews, we studied the flow of gas in accretion disks in binary star systems when the accreing object is a white dwarf, neutron star, or black hole.
TNF-α and cumulus cell-oocyte complex expansion
Ovulation is the process by which a fertilizable oocyte and surrounding somatic cumulus cells (the cumulus cell-oocyte complex; COC) are released form the ovary for fertilization. The microenvironment and selected signaling events within the COC of preovulatory follicles are essential for proper formation of an extracellular matrix critical for ovulation. This area links to videos showing that blocking the activity of the TSG-6 link module disrupts normal COC expansion.
Shotgun antisense allows us to identify an interesting mutant in the morning, start sequencing the gene’s DNA in the afternoon.