BIO-8022 Biological membranes and their proteins - 5 stp

Membrane proteins are responsible for most communications between cells or cellular compartments. They ensure the passage of ions, metabolites or other molecules and permit signaling. They are involved in many fundamental processes (neurotransmission, bioenergetics, cell development and many others). Their mechanisms of action rely on minute atomic properties as well as on large conformational changes occurring within their structures. However, in contrast to soluble proteins, the function of a membrane protein is also strongly dependent on the properties of the lipidic membrane in which the protein is embedded. Because of the essential roles of membrane proteins in most fundamental biological processes, they constitute major drug targets, and it is estimated that nearly 60% of the currently approved drugs target membrane proteins. The course is an introduction to biological membranes. Students will learn about the composition of these membranes, lipids and proteins, the behavior of lipids and their phase diagrams, the role of proteins and the different types of functions they achieve. The course will give a complete overview from genes (and how to recognize genes encoding membrane proteins) to the synthesis and insertion pathways of membrane proteins to their target membrane. The courses will be of general interest to biology or chemistry students, with a particular focus on membrane processes deciphered at the molecular level. The course will also bring insights into biophysics of proteins. The course is held for 2 weeks and contains 14 lectures and 5 days in the lab.

Lectures are grouped in 4 parts: 1) Lipids and Membranes (4 lectures) Lipids and Biomembranes: definition of different classes of lipids, different phases formed by lipids in water Properties of biological membranes: lipid composition and membrane proteins Examples of different membranes in eukaryotic cells (specific lipids, ratio between lipids and proteins) Lipids of organisms living under extreme conditions (low temperature, high pressure) how to maintain the fluid phase 2) Membrane proteins in vivo and main biological functions (5 lectures) Finding membrane protein encoding genes within genomes, TM predictions, Topologies of membrane proteins Synthesis and transport to membranes Main functional classes: Transporters, Receptors, Ion channels, Enzymes Protein structures and their implications in function and dynamics 3) Methods for studying membranes and membrane proteins: biochemistry, structural biology and biophysics (4 lectures) Biochemistry of membrane proteins: Solubilization, purification, crystallization Properties and role of detergents and surfactants Liposomes and functional assays Biophysical methods to study membranes Single molecule fluorescence to understand membrane proteins in cells (dynamics, segregation, oligomerization) 4) Membrane proteins and drug design (1 lecture) Which targets? Identification of new hits Strategy for rational drug design

Lab exercises will be based on AcrB a multidrug transporter from E. coli, and will comprise: 1) Membrane preparation starting from cells overexpressing AcrB 2) Solubilization of membranes, purification of AcrB with affinity columns, test of a few detergents 3) Characterization of the purified protein,SDS-Page, Western Blot, Thermal stability 4) Crystallization of AcrB     5) Reconstitution into liposomes, testing protein incorporation by sucrose gradient and identification of the fractions.

Who can apply as a singular course student:

• PhD student enrolled at another institution than UiT. PhD students must upload a document from their university stating that there are registered PhD students. This group of applicants does not have to prove English proficiency and are exempt from semester fee.
• Holders of a master´s degree of five years or 3+2 years (or equivalent) may be admitted. These applicants must upload a Master´s Diploma with Diploma Supplement / English translation of the diploma. Applicants from listed countries must document proficiency in English. To find out if this applies to you, see the following list: Proficiency in English must be documented - list of countries. For more information on accepted English proficiency tests and scores, as well as exemptions from the English proficiency tests, please see the following document:  Proficiency in english - PhD level studies

The course will be arranged with a maximum of 10 and minimum of 3 students.

If more than 10 applicants, priority will be given as follows:

1. Participants admitted to the PhD programme at UiT

2. Participants in the Associate Professor programme (Førstelektorprogrammet)

3. PhD candidates from other universities

4. People with a minimum of a Masters degree (or equivalent), who have not been admitted to a PhD programme

The student will get:

• extensive knowledge on lipids constituting biological membranes and the different phases they are able to form
• profound insight into membrane proteins: how to recognize membrane proteins from genomes and what are the expected topologies, how they are synthesized in cells, which are the main functions fulfilled by membrane proteins
• knowledge of the methods that are adapted to study membranes and membrane proteins, from biochemistry, biophysics and structural biology
• insight into the process of drug design and knows which classes of membrane proteins constitute interesting targets
• experience with the use of detergents for the solubilization of biological membranes and their purification, as well as insight into the crystallization process

The student

• will acquired basic knowledge on the chemical nature and physical properties of lipid and detergent molecules
• can outline the main topologies encountered in structures of membrane proteins
• will know the main steps involved in membrane protein synthesis from the ribosome to protein insertion into the target membrane
• will acquire an overall overview of the main technics to study isolated membrane proteins or biological membranes

The student

• Understands the relevance of membrane proteins in fundamental biological pathways and their implications in pathologies
• Understands the potential exploitation of membrane proteins for medical or biotechnical applications
• Knows how to read a scientific text (report, or publication) related to membrane studies

Written exam approximately 2 weeks after the course. Grade: pass/fail.

Coursework requirements:

Requires that a minimum of 80% of the theoretical and practical parts of the course has been completed and that lab work has been reported satisfactorily. PhD students have to attend an additional seminar where they present 2-3 scientific publications covering particular topics of the course.

Re-sit exam:

There will be a re-sit examination for students that did not pass the previous ordinary examination.

The date for the exam can be changed. The final date will be announced at your faculty early in May and early in November.