Epithelia are a premier animal innovation, separating us from the outside world & demarcating body compartments. To organize individual cells into epithelia, animals evolved specialized machinery mediating adhesion cell to cell & of cells to underlying extracellular matrix 1/n These cell junctions link to the cytoskeleton, providing structural support and, in the case of the Actin and myosin cytoskeleton, generating force to drive cell shape change and motility 2/n

Theodore Boveri was one of the founders of cell biology, who work on chromosome segregation in embryonic development was foundational. In 1914 he made a speculative leap: Perhaps chromosome mis-segregation also was a cause of cancer 1/n
journals.biologists.com/jcs/article/12…
We're now many decades into the realization that virtually all cancers exhibit genome instability, and that gain or loss of chromosomes or chromosome arms (aneuploidy) is a very common feature 2/n

Epithelial tissues are one of the key innovations of the animal lineage, creating barriers separating inside from outside, and, in more complex animals, forming the architecture of tubular organs from blood vessels to the kidney to liver. 1/n Two key roles of epithelia as barriers between body compartments are to regulate transport across the epithelium & provide a mechanical barrier. Cell junctions are the key. Tight junctions mediate the first task while adherens junctions & desmosomes mediate the second 2/n

Anyone who has taken a biology class has seen a diagram like this, with the kidney-bean mitochondria and the shell of endoplasmic reticulum around the nucleus (thanks )--but we now know these images are wildly oversimplified 1/n biologydictionary.net/animal-cell/
Mind-blowing advances in microscopy have given us more and more detailed images of cellular architecture, revealing complexity and dynamics. e.g. 2/n nature.com/articles/ncomm…

It's been many decades since I took Biochemistry and the details have become a bit vague, so its sometimes challenging for me to wade through the surge of publications on "metabolomics" 1/n It was thus both fun and fascinating to read a recent paper that addressed these issues in a novel yet very accessible way 2/n
pubmed.ncbi.nlm.nih.gov/36893255/

I'll admit to being skeptical about "synthetic biology", wondering if it's just buzz words, but this recent paper from Daniels et al. blew me away with its combination of novel insights into cell signaling circuitry & its clinical potential 1/n
pubmed.ncbi.nlm.nih.gov/36480602/ Chimeric antigen receptors (CARs) combine engineered antibodies as extracellular domains linked to increasingly complicated intracellular signaling domains. Chimeric antigen receptor T cells have proved effective in B cell malignancies. 2/n

The events at the UC system have me reflecting on what a huge difference the @UAW made for our family. After their attempt at farming failed, my parents moved to the Twin Cities, and started over. Both worked throughout my childhood, with my dad often working two jobs 1/6 Thankfully, with help from my uncle, my dad got a full time job with General Motors, where he joined the @UAW. Looking back, I can see more clearly how close to the edge our family likely was during my childhood, but that began to change as I neared college. 2/6

Super excited about today's @UNC_Biology Seminar, “Environmental Control of Cell Behavior”, featuring our star alum Minna Roh-Johnson. Minna was a great colleague who did amazing work in the Goldstein lab, and its been so much fun to see her career develop 1/3 She & her lab have broad interests in cancer cell & developmental biology. They use a wide variety of model organisms, including Zebrafish, Mice, and Dictyostelium to study how normal and cancer cells migrate and interact with their microenvironment. 2/3
roh-johnson.biochem.utah.edu

Building the embryo body plan involves dramatic cell shape change & cell migration. Many labs are working to define underlying mechanisms. However, we often neglect an equally dramatic cell shape that continues throughout life: that required for cell proliferation 1/n In epithelial tissues, cells are connected by cell-cell junctions. In more static tissues their actomyosin cytoskeletons exert balanced forces upon one another, maintaining uniform cell shapes. 2/n

The effect of socioeconomic background and parentally education on the ability to navigate your way to a PhD is, to me, both not surprising and surprising. 1/8
washingtonpost.com/business/2022/… As a first generation college student entering a PhD program in 1981 I was immediately struck by how many of my grad school classmates came from academic backgrounds. These data fit that: in Biology (one of the 11 fields in the middle), it looks like they would have been ~50% 2/8

One of the great mysteries of our planet is how life emerged from a soup of macromolecules. It requires the "invention" of replication, transcription and translation. Some have speculated life began more simply, in an "RNA/peptide world" 1/8 These RNAs would need to evolve the ability to replicate, and ultimately to construct proteins. The machine that accomplishes this now, the ribosome, is incredibly complex, using two large RNAs as catalysts and smaller tRNAs to deliver amino acids. 2/8

One of biology's great mysteries is "gene regulation", how cells choose which genes to express, when & at what level. It's a question that intrigued me since I started my grad work in a lab cloning the fly Hox genes. Ed Lewis's genetic analysis suggested great complexity 1/14 Meanwhile, down the hall Kevin Struhl's lab was beginning to unveil the basic mechanisms of gene regulation in eukaryotes, using budding yeast, suggesting a simpler picture 2/14

Carol Ann led a lovely @NCBotGarden hike up Little Long Mountain the the Uwharries, about 90 minutes SW of Chapel Hill. The wildflowers started above the parking lot as we waited-partridgeberry, fairy wand, Galax & Hexastylis minor. I may have seen Stewart ovata (foliage) 😀🤞1/8 I strolled down Flint Hill Road for some more flowers before the hike: Calycanthus, Scutellaria ovata, Coreopsis auriculata, and (in my favorite genus) Asclepias variegata! 2/8

Quite a day of weather in the Piedmont today. As we drove in there were dark clouds with patches of sun 1/4 We'd planned on heading to the @CarrboroMarket but by the time we got to town it was raining cats and dogs so we detoured across town to the @chpublib, where not a drop had fallen. 2/4

The Twitter discussion about postdoc searches was informative & very eye-opening.Coming from a particular R1 environment I was surprised at the diversity of thoughts on this. Before I exit this discussion I wanted to summarize my own thoughts-warning, its a long thread —they are specific to the US, my field and institutions like mine (@UNC)