title: Fundamental origins and limits for scaling a maternal morphogen gradient.
abstract: Tissue expansion and patterning are integral to development; however, it is unknown quantitatively how a mother accumulates molecular resources to invest in the future of instructing robust embryonic patterning. Here we develop a model, Tissue Expansion-Modulated Maternal Morphogen Scaling (TEM(3)S), to study scaled anterior-posterior patterning in Drosophila embryos. Using both ovaries and embryos, we measure a core quantity of the model, the scaling power of the Bicoid (Bcd) morphogen gradient's amplitude nA. We also evaluate directly model-derived predictions about Bcd gradient and patterning properties. Our results show that scaling of the Bcd gradient in the embryo originates from, and is constrained fundamentally by, a dynamic relationship between maternal tissue expansion and bcd gene copy number expansion in the ovary. This delicate connection between the two transitioning stages of a life cycle, stemming from a finite value of nA~3, underscores a key feature of developmental systems depicted by TEM(3)S.
authors: Division of Biomedical Informatics, Cincinnati Children's Research Foundation, 3333 Burnet Avenue, Cincinnati, Ohio 45229, USA.
authors: Feng
authors: F
authors: He
authors: 1] Division of Biomedical Informatics, Cincinnati Children's Research Foundation, 3333 Burnet Avenue, Cincinnati, Ohio 45229, USA [2] State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Beijing 100101, China [3] University of Chinese Academy of Sciences, Beijing 100080, China.
authors: Chuanxian
authors: C
authors: Wei
authors: 1] Division of Biomedical Informatics, Cincinnati Children's Research Foundation, 3333 Burnet Avenue, Cincinnati, Ohio 45229, USA [2] State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Beijing 100101, China [3] University of Chinese Academy of Sciences, Beijing 100080, China.
authors: Honggang
authors: H
authors: Wu
authors: Division of Biomedical Informatics, Cincinnati Children's Research Foundation, 3333 Burnet Avenue, Cincinnati, Ohio 45229, USA.
authors: David
authors: D
authors: Cheung
authors: 1] State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Beijing 100101, China [2] Sino-French Hoffmann Institute, Guangzhou Medical University, 195 Dongfengxi Road, Guangzhou 510182, China.
authors: Renjie
authors: R
authors: Jiao
authors: 1] Division of Biomedical Informatics, Cincinnati Children's Research Foundation, 3333 Burnet Avenue, Cincinnati, Ohio 45229, USA [2] Division of Developmental Biology, Cincinnati Children's Research Foundation, 3333 Burnet Avenue, Cincinnati, Ohio 45229, USA.
authors: Jun
authors: J
authors: Ma
mesh_terms: D000818:Animals; D056915:DNA Copy Number Variations; D004330:Drosophila / Q000235:genetics*; D029721:Drosophila Proteins; D004331:Drosophila melanogaster; D004625:Embryo, Nonmammalian; D005260:Female; D018398:Homeodomain Proteins / Q000235:genetics; D008954:Models, Biological; D009024:Morphogenesis / Q000235:genetics*; D010053:Ovary; D015534:Trans-Activators / Q000235:genetics
chemical_list: D029721:Drosophila Proteins; D018398:Homeodomain Proteins; D015534:Trans-Activators; C056478:bcd protein, Drosophila