Resonctructing signaling pathways from RNAi data using genetic algorithms

Download
2011
Ayaz, Eyüp Serdar
Cell signaling is a list of chemical reactions that are used for intercellular and intracellular communication. Signaling pathways denote these chemical reactions in a systematic manner. Today, many signaling pathways are constructed by several experimental methods. However there are still many communication skills of cells that are needed to be discovered. RNAi system allows us to see the phenotypes when some genes are removed from living cells. By observing these phenotypes, we can build signaling pathways. However it is costly in terms of time and space complexity. Furthermore, there are some interactions RNAi data cannot distinguish that results in many different signaling pathways all of which are consistent with the RNAi data. In this thesis, we combine genetic algorithms with some greedy approaches to find the topologies that fit the Boolean single knock-down RNAi experiments. Our algorithm finds nearly all of the results for small inputs in a few minutes. It can also find a significant number of results for larger inputs. Then we eliminate isomorphic topologies from the output set of this algorithm. This process fairly reduces the number of topologies. Afterwards we offer a simple scheme for suggesting new wet-lab RNAi experiments which is necessary to have a complete approach to find the actual network. Also we describe a new activation and deactivation model for pathways when the activation of the phenotype after RNAi knock-downs are given as weighted variables. We adapt the first genetic algorithm approach to this model for directly finding the most possible network.

Suggestions

Visualization of interactions between fluorescently tagged g protein α11, α12/13 subtypes and adenosine 2a, dopamine 2 or homodimer adenosine 2a/2a receptors
Kostromin, İrmak Begüm; Son, Çağdaş Devrim; Department of Biology (2018)
G-Protein-coupled receptors (GPCRs) belong to one of the largest family of cell surface receptors, which transmit extracellular signals to intracellular responses by interacting with G- proteins. The G proteins are known as molecular switches that regulates different pathways via control of secondary messengers and signaling proteins. Adenosine 2A (A2A) and Dopamine 2 (D2) receptors belong to G-Protein-coupled receptors (GPCRs) family and are located mostly in striatopallidal γ-aminobutyric acid (GABA) cont...
Integration of clavaminate synthase 2 gene into the chromosome of an industrial strain of Streptomyces Clavuligerus for enhanced clavulanic acid production
Vanlı, Güliz; Özcengiz, Gülay; Özkan, Melek; Department of Biotechnology (2010)
Streptomyces clavuligerus is a gram-positive, filamentous bacterium which has a great ability to produce secondary metabolites including isopenicillin N, cephamycin C and a beta-lactamase inhibitor clavulanic acid. Clavulanic acid (CA) which is a bicyclic beta-lactam, inhibits most of class A beta-lactamases by binding irreversibly to the serine hydroxyl group at the active center of beta-lactamases and resulting in the stable acyl-enzyme complexes. Clavaminate synthase (CAS) is one of the best characterize...
Thermodynamics and Kinetics of Association of Antibiotics with the Aminoglycoside Acetyltransferase (3)-IIIb, a Resistance-Causing Enzyme
Norris, Adrianne L.; Özen, Can; Serpersu, Engin H. (2010-05-18)
The thermodynamic and kinetic properties of interactions of antibiotics with the aminoglycoside acetyltransferase (3)-IIIb (AAC) are determined with several experimental methods. These data represent the first such characterization of an enzyme that modifies the 2-deoxystreptamine ring common to all aminoglycoside antibiotics. Antibiotic substrates For AAC include kanamycin A, kanamycin B, tobramycin, sisomicin, neomycin B, paromomycin, lividomycin A, and ribostamycin. Kinetic studies show that kanamycin gr...
DynaDom: structure-based prediction of T cell receptor inter-domain and T cell receptor-peptide-MHC (class I) association angles
Hoffmann, Thomas; Marıon, Antoıne; Antes, Iris (Springer Science and Business Media LLC, 2017-02-02)
Background: T cell receptor (TCR) molecules are involved in the adaptive immune response as they distinguish between self- and foreign-peptides, presented in major histocompatibility complex molecules (pMHC). Former studies showed that the association angles of the TCR variable domains (Va/V beta) can differ significantly and change upon binding to the pMHC complex. These changes can be described as a rotation of the domains around a general Center of Rotation, characterized by the interaction of two highly...
Self-consistent calculation of semiconductor heterojunctions using quantum genetic algorithm
Sahin, M; Tomak, Mehmet (2002-10-20)
In this study, we have investigated the ground state energy level of electrons in modulation doped GaAs/AlxGa1-xAs heterojunctions. For this purpose, Schrodinger and Poisson equations are solved self consistently using quantum genetic algorithm (QGA). In this way, we have found the potential profile, the ground state subband energy and their corresponding envelope functions, Fermi level, and the amount of tunneling charge from barrier to channel region. Their dependence on various device parameters are also...
Citation Formats
E. S. Ayaz, “Resonctructing signaling pathways from RNAi data using genetic algorithms,” M.S. - Master of Science, Middle East Technical University, 2011.