Christine Jacobs-Wagner (Yale, HHMI) 1: The role of spatial organization in bacterial cell function

www.ibiology.org/microbiology...
Talk Overview:
Most bacterial cells are many, many times smaller than eukaryotic cells. Since they have no membrane-bound internal organelles, their cellular organization also appears much simpler. Over the last decade, however, scientists have come to understand that that bacterial cells have a cytoskeleton. Jacobs-Wagner explains that bacterial homologues of tubulin (FtsZ) and actin (MreB) are critical for cell division amongst other functions. Crescentin, a bacterial counterpart of intermediate filament proteins, gives Caulobacter crescentus its crescent shape. In addition, bacteria exhibit sophisticated spatial organization; proteins can be spatially patterned and the bacterial chromosome forms an organized structure that locates genes at specific positions in the cell.
In her second lecture, Jacobs-Wagner tells us about research in her lab into how bacterial chromosomal DNA is segregated. For distances as small as those found in a bacterial cell, diffusion can successfully distribute high copy number molecules throughout the cell. However, diffusion cannot effectively separate 2 chromosomes such that after cell division each daughter cell is likely to have one chromosome. To do this job, bacteria have evolved a partitioning system called ParABS. Jacobs-Wagner describes the how the ParABS system works to separate chromosomal DNA in C. crescentus.
Speaker Biography:
Christine Jacobs-Wagner received her BS in biochemistry from the University of Liège in Belgium and her PhD from the University of Liège and the Karolinska Institute. As a post-doctoral fellow she worked with Lucy Shapiro at Stanford University. In 2001, Jacobs-Wagner moved to Yale University where she is currently a Professor of Molecular, Cellular and Developmental Biology and Director of the Microbial Sciences Institute. Jacobs-Wagner also has been a Howard Hughes Medical Institute Investigator since 2008. Her lab investigates the spatial and temporal organization of molecules inside bacteria and the impact of this organization on bacterial function and behavior.
Jacobs-Wagner’s pioneering research has been recognized with a Pew Scholar Award, the American Society for Cell Biology Women in Cell Biology Junior Award, and the Eli Lilly Award from the American Society of Microbiology.

[@shimason7617]

Thank you so much. I am so excited to know such a beautiful organization that bacteria have in their body.

[@aepceo1]

Thank god for you, Christine! I'm taking a high level (BIO471) course that deals with this exact set of molecular mechanisms for fission but videos on it are extremely rare with this level of detail. Thanks!

[@StewartChaimson]

Great job, thank you very much.

[@paulocaldas8533]

it's been a while, but does anyone know the source of that FtsZ-YFP division movie?

[@EccentricAuntWanda1]

Nicely done!

[@yangliu1985]

This is helpful!

[@rogerscottcathey]

Nobody on the entire internet knows how we got the LABEL MreB. Yes we know it's an actin homologue, but WHAT DO THE LETTERS "M"-"r"-"e" and "B" STAND FOR? Can anyone, possibly . . help me here?

[@OfArmadillo]

The 'Mre' name comes from a paper - Matsuhashi et al where they identified two gene regions which they labelled Mbe and Mrd. The MreB name specifically comes in a paper (Doi et al., 1988) where a specific gene in this Mre region was investigated and given the identifier 'B', giving full name MreB. I can't quickly find the paper by Matsuhashi et al but the link to the Doi et al paper is www.ncbi.nlm.nih.gov/pmc/articles/PMC211501/?page=1
Hope this helps, if you want to get to the bottom of where the 'Mre' name comes from, you may need to find a copy of the Matsuhashi paper. It was published in 1982 so finding it online may be difficult.

[@rogerscottcathey]

@@OfArmadillo : You're amazing! Thanks!