PhD ceremony: C. Madeti Jyothi, 16.15 uur, Academiegebouw, Broerstraat 5, Groningen
Thesis: The clock in the cell: entrainment of the circadian clock in Neurospora crassa
Promotor(s): mw.prof. M. Merrow, prof. T. Toenneberg
Faculty: Mathematics and Natural Sciences
Entrainment of the circadian clock in Neurospora crassa
Since reports of daily leaf movements 2000 years ago, a so-called circadian clock (‘circa diem’ meaning ‘about a day’) has been described in organisms from almost all phyla. The work Cornelia Madeti presented in this thesis gives special emphasis on the circadian clock in the fungus Neurospora crassa, a rather simple cellular system. Neurospora was used to elucidate basic clock mechanisms that are comparable to those in more complex organisms. To that end, Madeti investigated chronoecological questions as well as questions concerning cellular mechanisms.
A worldwide collection of Neurospora crassa strains from the wild was chronotyped and researched by her on how the circadian clock is related to the latitude of origin. She found correlations in some but not all cases dependent on the zeitgeber (light or temperature) applied. Furthermore, she found –here and also in several other experiments- that phase of entrainment and period are not always correlated. This speaks for encoding of these clock characteristics at different locations in the circadian system: different chronotypes can be the result of different period lengths but also of alterations in inputs or the coupling of outputs to the oscillator.
Only few components of circadian clocks are known to date. To find novel clock genes, Madeti applied two methods, one where in a QTL-analysis clock gene candidates can be found with help of the cosegregating circadian phenotypes and another, where a candidate clock gene is mutated. Here, a lack of cryptochrome leads almost exclusively to a delayed chronotype, suggesting it being a clock gene.
After a decade of preparations, it’s finally time: on the evening of 20 September the German icebreaker Polarstern departs from the Norwegian port of Tromsø. Escorted by the Russian icebreaker Akademik Fedorov, she will set sail for the Central Arctic...
Noorderlicht and the University of Groningen (RUG) continue their collaboration in the ‘Imagining Science’ series. Each year they commission a photographer to depict a scientific research field in relation to the Noorderlicht festival-theme of the year...
Banks with a high sustainability score have a lower default risk. In addition, the most sustainable banks help to reduce the systemic risk of the financial system as a whole. These are the conclusions of Bert Scholtens, Professor of Sustainable Banking...