Future Seminar Dates

Title:   "Insulin sensitivity and reactive oxygen species"

Speaker:   Professor Mark Kearney, University of Leeds.

Time:   12noon - 1:00pm

Venue:   Lecture Theatre 3, F Floor Medical School.

Abstract:   New treatments for the cardiovascular complications of type 2 diabetes are urgently required. Insulin resistance defined as a loss of normal temporo-spatial activation of insulin signalling pathways is a hallmark of type 2 diabetes. We have examined the effects of manipulating insulin sensitivity specifically in the endothelium in vivo. Our findings reveal a novel effect of insulin sensitivity on endothelial reactive oxygen species generation and vascular function.

Title:   "A role for Gfi1 in blood stem cells emerging from the dorsal aorta"

Speaker:   Dr Martin Gering. Queen's Medical Centre, University of Nottingham.

Time:   12noon - 1:00pm

Venue:   Lecture Theatre 3, F Floor Medical School.

Abstract:   In vertebrates, haematopoietic stem cells (HSCs) form during embryogenesis and maintain our blood system throughout life. Using a transposon-based gene trap approach in zebrafish, we identified a transgenic line called qmc551 that expresses an egfp reporter gene at the earliest stages of HSC development, the time when HSCs form from haemogenic endothelial cells in the ventral wall of the dorsal aorta. Inverse PCR suggested that the gene trapped in qmc551 is gfi1.1. Indeed, the green fluorescence co-segregates in the progeny with the presence of the transposon in gfi1.1, and the pattern of GFP expression faithfully recapitulates the expression pattern of endogenous gfi1.1 in the blood, the inner ear, the lateral line organ, the pancreas and the intestine. Within the blood, GFP expression is initiated in the embryo and is maintained into adulthood, with GFP-positive cells found in the kidney, the adult site of haematopoiesis. Interestingly, homozygous transgenics are viable and fertile, suggesting that Gfi1.1 expression is not affected or that its loss is compensated for in the transgenic fish. Given that this transgenic line labels HSC progenitors earlier and more specifically than any other line published to date it constitutes a unique resource for the isolation and characterisation of the earliest HSC progenitors.