scholarly journals Symmetry breaking in the embryonic skin triggers a directional and sequential front of competence during plumage patterning

2018 ◽  
Author(s):  
Richard Bailleul ◽  
Carole Desmarquet-Trin Dinh ◽  
Magdalena Hidalgo ◽  
Camille Curantz ◽  
Jonathan Touboul ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Natural Variation ◽  
Theoretical Models ◽  
Self Organization ◽  
Final States ◽  
Traveling Front ◽  
Embryonic Skin ◽  
Pattern Forming ◽  
Reproducible Manner

ABSTRACTThe development of an organism involves the formation of patterns from initially homogeneous surfaces in a reproducible manner. Simulations of various theoretical models recapitulate final states of natural patterns1-4 yet drawing testable hypotheses from those often remains difficult4,5. Consequently, little is known on pattern-forming events. Here, we extend modeling to reproduce not only the final plumage pattern of birds, but also the observed natural variation in its dynamics of emergence in five species. We built a unified model intrinsically generating the directionality, sequence, and duration of patterning, and used in vivo experiments to test its parameter-based predictions. We showed that while patterning duration is controlled by overall cell proliferation, its directional and sequential progression result from a pre-pattern: an initial break in surface symmetry launches a traveling front of increased cell density that defines domains with self-organizing capacity. These results show that universal mechanisms combining pre-patterning and self-organization govern the timely emergence of the plumage pattern in birds.

scholarly journals Design of biochemical pattern forming systems from minimal motifs

eLife ◽  
2019 ◽  
Vol 8 ◽  
Author(s):  
Philipp Glock ◽  
Fridtjof Brauns ◽  
Jacob Halatek ◽  
Erwin Frey ◽  
Petra Schwille
Keyword(s):  
Pattern Formation ◽  
Self Organization ◽  
Binding Motifs ◽  
Biochemical Systems ◽  
Systematic Understanding ◽  
Pattern Forming ◽  
Underlying Mechanisms ◽  
Complex Features

Although molecular self-organization and pattern formation are key features of life, only very few pattern-forming biochemical systems have been identified that can be reconstituted and studied in vitro under defined conditions. A systematic understanding of the underlying mechanisms is often hampered by multiple interactions, conformational flexibility and other complex features of the pattern forming proteins. Because of its compositional simplicity of only two proteins and a membrane, the MinDE system from Escherichia coli has in the past years been invaluable for deciphering the mechanisms of spatiotemporal self-organization in cells. Here, we explored the potential of reducing the complexity of this system even further, by identifying key functional motifs in the effector MinE that could be used to design pattern formation from scratch. In a combined approach of experiment and quantitative modeling, we show that starting from a minimal MinE-MinD interaction motif, pattern formation can be obtained by adding either dimerization or membrane-binding motifs. Moreover, we show that the pathways underlying pattern formation are recruitment-driven cytosolic cycling of MinE and recombination of membrane-bound MinE, and that these differ in their in vivo phenomenology.

scholarly journals Design of biochemical pattern forming systems from minimal motifs

2019 ◽  
Author(s):  
Philipp Glock ◽  
Fridtjof Brauns ◽  
Jacob Halatek ◽  
Erwin Frey ◽  
Petra Schwille
Keyword(s):  
Pattern Formation ◽  
Self Organization ◽  
Binding Motifs ◽  
Biochemical Systems ◽  
Systematic Understanding ◽  
Pattern Forming ◽  
Underlying Mechanisms ◽  
Complex Features

AbstractAlthough molecular self-organization and pattern formation are key features of life, only very few pattern-forming biochemical systems have been identified that can be reconstituted and studied in vitro under defined conditions. A systematic understanding of the underlying mechanisms is often hampered by multiple interactions, conformational flexibility and other complex features of the pattern forming proteins. Because of its compositional simplicity of only two proteins and a membrane, the MinDE system from Escherichia coli has in the past years been invaluable for deciphering the mechanisms of spatiotemporal self-organization in cells. Here we explored the potential of reducing the complexity of this system even further, by identifying key functional motifs in the effector MinE that could be used to design pattern formation from scratch. In a combined approach of experiment and quantitative modeling, we show that starting from a minimal MinE-MinD interaction motif, pattern formation can be obtained by adding either dimerization or membrane-binding motifs. Moreover, we show that the pathways underlying pattern formation are recruitment-driven cytosolic cycling of MinE and recombination of membrane-bound MinE, and that these differ in their in vivo phenomenology.

Lentiviral-Mediated Beclin-1 Overexpression Inhibits Cell Proliferation and Induces Autophagy of Human Esophageal Carcinoma Eca109 Cell Xenograft in Nude Mice

2020 ◽  
Vol 15 (1) ◽  
pp. 70-77
Author(s):  
Junhe Zhang ◽  
Weihua Dong
Keyword(s):  
Growth Rate ◽  
Cell Proliferation ◽  
Esophageal Carcinoma ◽  
Nude Mice ◽  
Beclin 1 ◽  
Control Group ◽  
Vector Group ◽  
Empty Vector ◽  
Empty Vector Group

Background: Esophageal carcinoma is one of the common malignant tumors in digestive tract. BECLIN-1 is a key gene that regulates autophagy, and its abnormal expression may be related with many human tumors. However, the mechanism of BECLIN-1 in esophageal carcinoma remains unknown. Objective: In this study, we explored the effect of BECLIN-1 overexpression on tumor growth in mice with esophageal carcinoma and its mechanism. Methods: Recombined lentiviral vector containing BECLIN-1 was used to transfect human esophageal carcinoma Eca109 cells and establish stable cell line. qRT-PCR was used to detect BECLIN-1 mRNA level in the transfected Eca109 cells, CCK-8 assay was used to detect cell proliferation. Beclin-1, P62 and LC3-II protein expression levels in Eca109 cells were detected using Western blot analysis. Subcutaneous xenograft nude mice model of human esophageal carcinoma was established, and the tumor growths in Beclin-1 group, control group and empty vector group were monitored. Beclin-1 protein expression in vivo was detected by immunohistochemistry. Results: Beclin-1 mRNA and protein were overexpressed in Eca109 cells. Compared with empty vector group, the growth rate of cells transfected with BECLIN-1 decreased significantly. Compared with the control group and empty vector group, the expression level of P62 protein in beclin-1 group was significantly decreased, while the expression level of LC3-II protein was significantly increased. The tumor growth rate in nude mice of Beclin-1 group was significantly lower than that of the control group and empty vector group, and Beclin-1 protein was mainly expressed in Beclin-1 group in vivo. Conclusion: BECLIN-1 can induce autophagy in esophageal carcinoma Eca109 cells, and it can significantly inhibit the growth of esophageal carcinoma.

Sign in / Sign up

Export Citation Format

Share Document