Studies on a variety of highly regenerative tissues, including the central nervous system（CNS） in non-mammalian vertebrates, have consistently demonstrated that tissue damage induces the formation of an ionic curren...Studies on a variety of highly regenerative tissues, including the central nervous system（CNS） in non-mammalian vertebrates, have consistently demonstrated that tissue damage induces the formation of an ionic current at the site of injury. These injury currents generate electric fields（EF） that are 100-fold increased in intensity over that measured for uninjured tissue. In vitro and in vivo experiments have convincingly demonstrated that these electric fields（by their orientation, intensity and duration） can drive the migration, proliferation and differentiation of a host of cell types. These cellular behaviors are all necessary to facilitate regeneration as blocking these EFs at the site of injury inhibits tissue repair while enhancing their intensity promotes repair. Consequently, injury-induced currents, and the EFs they produce, represent a potent and crucial signal to drive tissue regeneration and repair. In this review, we will discuss how injury currents are generated, how cells detect these currents and what cellular responses they can induce. Additionally, we will describe the growing evidence suggesting that EFs play a key role in regulating the cellular response to injury and may be a therapeutic target for inducing regeneration in the mammalian CNS.展开更多
The MYB transcription factor genes play important roles in many developmental processes and various defense responses of plants. The shikimate pathway is a major biosynthetic pathway for the production of three aromat...The MYB transcription factor genes play important roles in many developmental processes and various defense responses of plants. The shikimate pathway is a major biosynthetic pathway for the production of three aromatic amino acids and other aromatic compounds that are involved in multiple responses of plants, including protection against UV and defense. Herein, we describe the characterization of the R2R3-MYB gene AtMYB15as an activator of the shikimate pathway in Arabidopsis. The AtMYB15 protein is nuclear localized and a transcriptional activation domain is found in its C-terminal portion. Northern blots showed that AtMYB15 is an early wounding-inducible gene. Resutls of microarray analysis, confirmed using quantitative real-time polymerase chain reaction, showed that overexpression of AtMYB15 in transgenic plants resulted in elevated expression of almost all the genes involved in the shikimate pathway. Bioinformatics analysis showed that one or more AtMYB15-binding AC elements were detected in the promoters of these upregulated genes. Furthermore, these genes in the shikimate pathway were also found to be induced by wounding. These data suggest an important role of AtMYB15as a possible direct regulator of the Arabidopsis shikimate pathway in response to wounding.展开更多
文摘Studies on a variety of highly regenerative tissues, including the central nervous system（CNS） in non-mammalian vertebrates, have consistently demonstrated that tissue damage induces the formation of an ionic current at the site of injury. These injury currents generate electric fields（EF） that are 100-fold increased in intensity over that measured for uninjured tissue. In vitro and in vivo experiments have convincingly demonstrated that these electric fields（by their orientation, intensity and duration） can drive the migration, proliferation and differentiation of a host of cell types. These cellular behaviors are all necessary to facilitate regeneration as blocking these EFs at the site of injury inhibits tissue repair while enhancing their intensity promotes repair. Consequently, injury-induced currents, and the EFs they produce, represent a potent and crucial signal to drive tissue regeneration and repair. In this review, we will discuss how injury currents are generated, how cells detect these currents and what cellular responses they can induce. Additionally, we will describe the growing evidence suggesting that EFs play a key role in regulating the cellular response to injury and may be a therapeutic target for inducing regeneration in the mammalian CNS.
基金Supported by the National Priority Basic Research Programs of People＇s Republic of China： Biosafety Study on GM0s of Agricultural Importance （001CB10902 to L-JQ）, the National Natural Science Foundation of China （30470358）, and the Excellent Young Teachers Program of M0E, China （to L-JQ）. Acknowledgements The authors thank Ms Li Zhang and Professor Meihua Liu （Peking University） for technical assistance.
文摘The MYB transcription factor genes play important roles in many developmental processes and various defense responses of plants. The shikimate pathway is a major biosynthetic pathway for the production of three aromatic amino acids and other aromatic compounds that are involved in multiple responses of plants, including protection against UV and defense. Herein, we describe the characterization of the R2R3-MYB gene AtMYB15as an activator of the shikimate pathway in Arabidopsis. The AtMYB15 protein is nuclear localized and a transcriptional activation domain is found in its C-terminal portion. Northern blots showed that AtMYB15 is an early wounding-inducible gene. Resutls of microarray analysis, confirmed using quantitative real-time polymerase chain reaction, showed that overexpression of AtMYB15 in transgenic plants resulted in elevated expression of almost all the genes involved in the shikimate pathway. Bioinformatics analysis showed that one or more AtMYB15-binding AC elements were detected in the promoters of these upregulated genes. Furthermore, these genes in the shikimate pathway were also found to be induced by wounding. These data suggest an important role of AtMYB15as a possible direct regulator of the Arabidopsis shikimate pathway in response to wounding.
