2003/07/22 by Alexei A. Koulakov, Koulakov, Alexei A., Dmitry N. Tsigankov +2
Biochemistry, Genetics and Molecular Biology · Neuroscience · Physics and Astronomy · #Axon Guidance and Neuronal Signaling #Biological Physics (physics.bio-ph) #Disordered Systems and Neural Networks (cond-mat.dis-nn) #FOS: Biological sciences #FOS: Physical sciences #Neuroscience and Neuropharmacology Research #Quantitative Biology (q-bio) #Zebrafish Biomedical Research Applications #cond-mat.dis-nn #physics.bio-ph #q-bio
paper · pdf · doi:10.48550/arxiv.physics/0307107
19 pages, 11 color figures
arxiv created 2003/07/22 · openalex publication_date 2003/07/22 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We present a theoretical model for retinocollicular map development, which can account for intriguing behaviors observed in gain-of-function experiments in knock-in mice by Brown et al., including bifurcation in heterozygous Isl2/EphA3 knock-ins. The model is based on known chemical labels, axonal repulsion/competition, stochasticity and uses Markov chain description. Our model suggests that the map in heterozygotes is single-valued in the temporal region of retina due to reduced gradient of ephrin in the corresponding region of SC. The remaining map is double-valued since the gradient of ephrin is high there. We predict therefore that if gradient of ephrin is reduced by a genetic manipulation, the single-valued region of the map should occupy a larger portion of temporal retina, i.e. the point of transition between single- and doulble-valued maps should move to a more nasal position in Isl2-EphA3 heterozygotes. We also discuss the importance of inhomogeneous EphA gradient and mapping in Isl2/EphB knock-ins.