Hot Topics in Bionanoscience

Course description: Speakers from all over the world are invited to present pedagogical introductions to their field with an emphasis on basic concepts. Apart from an introductory lecture, the participants of this course will have an additional discussion with the invited speaker. During that extra hour, they will discuss a recent paper and the holy grails of the field.

The first hour is a lecture and open for everyone to attend (in this case this BN seminar on "The mechanism and function of branching microtubule nucleation" at 12:45-13:45). The second hour is reserved as a discussion hour with the lecturer for the registered class of PhD students and postdocs.

Audience: Registered PhD students and postdocs (see registration form below).

Credits: Those participants who attended (pro-actively) a Hot Topics session will be awarded 1 Graduate School Credit (GSC).

Preparation: PhD students who have registered for the Hot Topics course need to prepare for the session by reading the articles that will soon be mentioned below. 

Date: Thursday 6 October 2022

Speaker: prof. Joshua Shaevitz (Princeton University, USA)

Host: Marianne Bauer

Required reading: Participants are required to prepare for this session by reading the following papers:

• Fast animal pose estimation using deep neural networks (Nature Meth., 2019);
• SLEAP: A deep learning system for multi-animal pose tracking (Nature Meth., 2022).
  

Abstract of the BN seminar: Microtubules are generated at centrosomes, chromosomes, and within spindles during cell division. Whereas microtubule nucleation at the centrosome is well characterized, much remains unknown about where, when, and how microtubules are nucleated at chromosomes. We have recently found that branching microtubule nucleation through the regulation of $\gamma$-TuRC can drive the assembly of acentrosomal spindles. A hydrodynamic instability produces droplets of the wetted protein TPX2 on microtubules which serve as nucleation sites for $\gamma$-TuRC binding and microtubule polymerization. To investigate this process near chromosomes, we reconstituted microtubule nucleation from purified chromosomes in meiotic Xenopus egg extract and found that chromosomes alone can form spindles. We visualized microtubule nucleation at chromosomes to find that this occurs through branching microtubule nucleation. The initial branches nucleate near and towards kinetochores, helping explain how kinetochores might be efficiently captured. By depleting molecular motors, we find that the organization of the resultant polar branched networks is consistent with a theoretical model where the effectors for branching nucleation, such as TPX2, are released by chromosomes, forming a concentration gradient around them that spatially biases branching nucleation. In the presence of motors, these branched networks are organized into multipolar spindles.

Registration
You can register for the course by filling in the form below. Your place at the course will be confirmed via email before the start of the Hot Topics session. In case there are too many registrants, a selection will be made based on first-come-first-served.

The data we collect are used for organizational purposes only and won't be stored longer than absolutely necessary. For more details, see our privacy statement.

Registration is closed. Please contact Celine Alkemade if you would still like to participate.