Internal Seminar: Yanagida Unit and Sinclair Unit

Join us for this February's Internal Seminar Series, from 17:00 to 18:00 in B250, central building.

This month's seminars feature the G0 Cell Unit (Mitsuhiro Yanagida) and the Mathematical Biology Unit (Robert Sinclair).

G0 Cell Unit (Mitsuhiro Yanagida)

Speaker : Romanas Chaleckis

Title : Individually variable compounds in human blood metabolome and their possible role in health and aging

Abstract : Metabolomics, a new branch of chemical biology, provides compositional and quantitative information about the state of organism or cell at the levels of metabolite constituents. Human blood is made up of plasma and red blood cells (RBCs). We could identify over 120 compounds from which over 50 were enriched in RBC. Several of these compounds were not previously reported in blood. By comparison of 30 persons blood metabolomes we were able to identify in healthy individuals 67 blood (27 RBC enriched) compounds, the levels of which are more changeable than experimental errors. Measurement of 10 individuals blood metabolomes for up to 2 years revealed that metabolite level variation within person is smaller than between persons. Certain metabolites showed individual levels such as 1,5-anhydroglucitol, ergothioneine, ophthalmic acid, dimethyl proline, pantothenate and caffeine. By comparing two age groups (29±4 and 81±7 years), we found that more than ten compounds displayed significant variations between the age groups. They include 1,5-anhydroglucitol, ophthalmic acid, dimethyl-guanosine, pantothenate and six unknown compounds. We discuss how these compounds are implicated in individual variations and age differences.

Mathematical Biology Unit (Robert Sinclair)

Speaker : Dr. Harshana Rajakaruna

Title : Do periodic temperature fluctuations drive marine copepod invasions? The case specific to Pseudodiaptomus marinus.

Abstract : Invasive biological colonizers propagated through human-mediated vectors, such as ship ballast-water, are bio-homogenizing the world’s oceans impacting the ecological structures and functions. Where do they come from, where do they go? What bio-physical mechanisms drive them to do what they do? Here, we present how periodic fluctuations of habitat temperatures impact the persistence and the potential range expansion of marine copepods, highlighting on the case specific to calanoid copepod P. marinus. We develop a biologically meaningful population persistence metric; a weighted net reproductive rate, which is a measure of the growth rate or the fitness of a population across a period of a temperature fluctuation; in consistent with advanced mathematical methods. We use this metric to understand the bio-geographical structure of the invasion dynamics of P. marinus. The model predicts a potential for the existing large gradient in periodic temperature fluctuations in the ocean, across ecoregions, to drive invasions from high to low amplitude temperature habitats within bandwidths of mean habitat temperatures. We show that this results from a multifold increase in the temperature-dependent cross-periodic fitness. The recent range expansion of P. marinus in Europe is consistent with the model predictions. This mechanistic basis may be generalized for species subject to similar periodic external forcing factors invading novel habitats, taking the advantage of their amplitude gradients.