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• Which pathway mediates sorting of endosomes cargo proteins into intraluminal vesicles of late endosomes? ESCRT pathway (=endosomal sorting complex required for transport)
• Name the ubiquitin-like protein that decorates autophagosomal membranes LC3 (ATG8)
• How do G proteins switch from the inactive into the active state? Activation of G proteins by exchange of GDP to GTP
• What are three components of the STAT pathway? Receptor, JAK, Stat
• Name three signaling pathways, which use phosphorylation of proteins for signal transduction. 1) MAPK pathway 2) Jak-Stat pathway 3) NFKB
• List minimum three ways by which the NF-kappaB signal pathway can be deregulated in lymphoma cells. -NFKBIA -NFKBIE -REL amplification -TNFAIP3 mutations -CYLD mutations
• Name minimum two examples for ligands of nuclear receptors 1) Sterols 2) Thyriod 3) Vitamin D 4) Cortisol 5) Retinoid
• Name minimum four steps in gene expression that can be regulated - Transcriptional control - RNA processing control - RNA transport and localization control - Translation control - mRNA degradation control - protein activity control
• Name two advantages for the fact that man transcription factors function as dimers. 1) many different DNA recognition patterns 2) increase and stabilize the binding
• Which is NOT one of the main steps in a DNA footprinting experiment? - Generation of specific DNA molecule with end labeling - Incubation with DNA binding protein to be investigated - Random cleavage of DNA with DNAse - Analysis of resulting DNA fragments by gel electrophoresis - Western blot analysis of the binding protein - Western blot analysis of the binding protein
• Name minimum three ways by which a repressor can inhibit transcription. - Competitive DNA binding (Repressor verdrängt den Aktivator) - Masking the activation surface (kann nicht am Mediator binden) - direct interaction with the general transcription factors (verbindet Kontakt zwischen Aktivator und   Mediator) - Recruitment of chromatin remodeling complexes (direkte Regulierung durch Strukturänderung) - recruitment of histone deacetylases (Repressor deacetyliert die Histone) - recruitment of histone methyl transferase
• Name examples of covalent histone modifications. 1) Methylation 2) Phosphorylation 3) Acetylation 4) Ubiquitylation
• Name examples of different non-membrane-delineated bodies present in the nucleus (besides the nucleoli) - Cajal bodies - Gemini of coiled bodies - Polymorphic interphase karyosomal association (PIKA) - Premyelocytic leukaemia (PML) bodies - Paraspeckles - Splicing speckles
• State the 6 main (architectural) structures of the nuclear pore complex 1) Cytoplasmic filament 2) Cytoplasmic ring 3) Cytoplasmic particles 4) Transporter 5) Spokes 6) Nuclear ring [7) Nuclear basket]
• Which structural motif of the NUPs is absolutely essential for nucleocytoplasmatic transport a) and b) what does it interact with a) FG repeats! b) with nuclear transporters (importin+exportin) and with other FG-repeats
• a) What molecule determines the directionality of nucleocytoplasmatic transport and b) which state does it mainly reside in which cellular compartment? a) RAN b) RAN-GTP in the Nucleus, RAN-GDP in the Cytosol
• a) Why do export complexes only assemble in the nucleus? b) and what complexes dissociate in the nucleus? Direktionalität durch Ran -> Ran-GEF nur im Nukleus, GAP nur im Cytoplasma
• What are the key substrates of the APC/C whose degradation induces a) anaphase onset and b) exit from mitosis? a) securin b) cyclin B (irreversible inhibition of Cdk1)
• Name the 3 main general ways of CdK-regulation 1) Phosphorylation 2) Degradation 3) CKI (Inhibitor protein)
• a) What is the enzyme that keeps CdK-Cyclin-B inactive in late G2 before entry into mitosis? b) What is the mechanism? a) Wee1 kinase b) deactivating phosporylation by Wee1
• What does the spindle assembly checkpoint monitor? ensuring bipolar attachment and controlling mitotic progression
• Which kinase at the centromere corrects erroneous spindle attachments by phosphorylating microtubule attachment sites at the kinetochores? Auroa B
• How is the type of cell-cell-communication called that occurs via direct contact between cells? juxtacrine
• Which are the two major components to tight junctions? claudin and occludin
• a) Which group of proteins are receptors for extracellular matrix proteins that form focal adhesion? b) What are their sub-units called? a) integrins b) α -sub-unit and β-sub-unit
• What is Haptotaxis? Directed migration on a gradient of ECM components
• Specify three types of ECM components 1) Core-protein 2) Linker 3) GAG
• Which part of microtubules protect them from depolymerization? GTP-Cap
• Direction of growth of microtubule filaments? polymerization predominantly at "+" End
• What formular describes actin polymerization in solution? v = kon * cmonomer v = koff (Depolymerisation)
• How Profilin "re-generate" actin monomers? Profilin catalyzes ADP/ATP exchange
• Which Rho GTPase pathway includes contractility of stress fibers? RhoA (Lamellipodium (Rak1), Filopodia -> Cdc42
• State the name of the physiological antagonist of inhibitors of apoptosis proteins (IAPs). Caspases
• The Bcl-2 family of proteins is involved in apoptosis regulation. Please state the name of one example each for a) antiapoptotic multidomain Bcl-2 proteins b) proapoptotic multidomain Bcl-2 proteins a) Bcl-2, Bcl-xL, Bcl-w (inhibitors) b) Bax / Bak (executors)
• State one biochemical function of the enzyme PTEN (phosphatase...10). 3-Lipidphosphatase (dephosphorylated) PtdIns(3,4,5)P3 -> PtdIns(4,5)P2 / (antagonize PI3K)
• state one biochemical function of the enzyme Ship 5-Lipidphosphatase (dephosphoryliert) PtdIns(3,4,5)P3 -> PtdIns(3,4)P2 / (antagonize PI3K)
• Bcl-2 proteins are involved of both, autophagy and apoptosis. State the name of one example of Bcl-2 proteins known to be involved in both processes. Bcl-2 and Bcl-xL
• Which one of the following statements is NOT correct? - Apoptosis, autophagy and necrosis can be distinguished by morphological criteria - Akl-1 mediated inhibition of Foxo3A participate in the inhibition of apoptosis - The DNA repair enzyme PARP-1 is inactivated during execution of programmed necrosis - Inhibition of mTOR is an important signal for the initiation of autophagy - Autophagy participates in the removal of damaged mitochondria The DNA repair enzyme PARP-1 is inactivated during execution of programmed necrosis
• Name the major phosphoinositide on early endosomes Clathrin
• What factor or event triggers the disassembly of the COP II coat and clathrin coat? sar1 hydrolyses GTP (the coat fall off)
• Which factor mediates fission of clathrin vesicles from the donor membrane and what is its catalytic activity? Dynamin --> Catalytic activity: GTP-Hydrolyse
• Which posttranslational modification regulates recruitment of endosomal cargo into the ESCRT pathway? Ubiquitination
• Name an adapter protein that mediates recruitment of ubiquitinated components to LC3/Atg8 on autophagosomal membranes. p62
• Define the following expressions: a) tumor b) metastasis c) benign a) tumor: "swelling" of tissues b) metastasis: secondary tumors in other parts of the bodyc) benign: non-invasive tumor mass
• Name an adapter protein that mediates recruitment of ubiquitinated components to LC3/Atg8 on autophagosomal membranes. p62
• Name the characteristics of malignant cells 1) Break physical barriers      2) Loss of tissue architecture   3) Enter blood vessels              4) Colonise territories reserved for other cells  5) unlimited proliferation
• What experimentally detectable phenomenon proves the clonal origin of cancer from a single abnormal somatic cell? tumor cells share common genetic defects
• What is the Philadelphia chromosome and with which disease is it associated? translocation of chromosome 9 and 22; Chronic myelogenous leukemia
• Carcinogenesis is a multistep process – which one of the following statements is NOT correct? -Cancer develops gradually from increasingly aberrant cells -Cancer requires the accumulation of multiple genetic/epigenetic changes within on cell -Cancer incidence is increased under conditions of increased mutagenesis -Cancer incidence is decreased under conditions of increased genomic instability -Cancer incidence is increased in families with inherited mutations in tumor suppressor genes or oncogenes -Cancer incidence is decreased under conditions of increased genomic instability
• How do microtubules localize signaling proteins to distinct places within the cell? transport vesicles as cargo via motor proteins OR depolymerization

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