doi:10.1093/jmcb/mju032
Journal of Molecular Cell Biology (2014), 6(4), 271
| 271
Editorial
Insights into complex processes of animal development Life is very complicated. Recently, a group of review
Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China E-mail: [email protected]
Organogenesis involves different layers of molecular regulations. For example, myogenesis has been reported under strict regulation of a gene regulatory network (Liu et al., 2012) and epigenetic factors (Neguembor et al., 2013). Studies in Dr Murga and Nieto-Va´zquez’s laboratories demonstrated that GPCR signaling pathway also participates in the myogenic process. The authors showed that disruption of G protein-coupled receptor kinase 2 (GRK2) resulted in a morphological defection with defective differentiation of somatic muscles and loss of fibers in both Drosophia and mouse. Furthermore, C2C12 myoblasts overexpressing a GRK2 kinase-deficient mutant generated immature myotubes, whereas GRK2 overexpression retarded the myotube differentiation. Finally, modulation of the p38MAPK pathway might contribute to a balanced GRK2 function in regulating skeletal muscle myogenesis. Given that the brain might be the most complicated part of the body, much attention has been attracted to unraveling previously unknown molecules or signaling events involved in brain development. In this issue, Dr Fan and Xu’s groups report their recent finding that TGF-b-activated kinase 1 (TAK1) is expressed in the axons of the mouse brain and can be activated by TGF-b. The activated TAK1 plays an important role in axonal growth during brain development, since TAK1 defect leads to delayed axon specification and outgrowth in brain-specific TAK1 knockout mice.
References Liu, Q.-C., Zha, X.-H., Faralli, H., et al. (2012). Comparative expression profiling identifies differential roles for Myogenin and p38a MAPK signaling in myogenesis. J. Mol. Cell Biol. 4, 386 – 397. Neguembor, M.V., Xynos, A., Onorati, M.C., et al. (2013). FSHD muscular dystrophy region gene 1 binds Suv4 – 20h1 histone methyltransferase and impairs myogenesis. J. Mol. Cell Biol. 5, 294 –307. Wu, J. (2013). Understanding and manipulating developmental complexity. J. Mol. Cell Biol. 5, 283.
# The Author (2014). Published by Oxford University Press on behalf of Journal of Molecular Cell Biology, IBCB, SIBS, CAS. All rights reserved.
Downloaded from http://jmcb.oxfordjournals.org/ by guest on April 16, 2015
Editor-in-Chief Jiarui Wu
papers on the complexity of various biological behaviors were published by Cell to celebrate its 40th anniversary. The developmental process must be one of the most complex events in multi-cellular organisms. JMCB has published several research papers in the previous Collection ‘Understanding and Mani-pulating Developmental Complexity’ (Wu, 2013). This issue publishes more articles focusing on the molecular mechanisms that regulate animal developmental processes, which should provide evidences for a better understanding of the developmental complexity. Large amounts of maternal products, such as RNAs and proteins, are stored in animal eggs to support the early embryonic development. As presented in this issue, Dr Meng’s group systematically analyzed the role of maternal Eomesodermin a (Eomesa), a T-box transcription factor, in the development of zebrafish embryos. The authors showed that maternal Eomesa was required for zygotic expression of the nodal genes ndr1 and ndr2, which are crucial factors for mesendoderm induction, as well as mxtx2, a regulator of nodal gene expression. They further demonstrated that Eomesa could directly bind to the promoter or enhancer of ndr1, ndr2, and mxtx2. Their findings reveal a conserved function of maternal transcription factors in regulating nodal gene expression and mesendoderm induction in the early development of animal embryos. Sperms, as the partner of eggs, also play critical roles in sexual reproduction. Acrosomal reaction of sperms is essential for the fertilization of eggs. In this issue, Dr Tomes’ laboratory reports that the small GTPase Rab3A behaves as a dual modulator during acrosomal exocytosis, which first exchanges GDP for GTP to accomplish docking of the acrosome to the plasma membrane and then undergoes GTP hydrolysis to allow fusion pores opening between the outer acrosomal and plasma membranes.
Journal of Molecular Cell Biology (2014), 6(4), 271
| 271
Editorial
Insights into complex processes of animal development Life is very complicated. Recently, a group of review
Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China E-mail: [email protected]
Organogenesis involves different layers of molecular regulations. For example, myogenesis has been reported under strict regulation of a gene regulatory network (Liu et al., 2012) and epigenetic factors (Neguembor et al., 2013). Studies in Dr Murga and Nieto-Va´zquez’s laboratories demonstrated that GPCR signaling pathway also participates in the myogenic process. The authors showed that disruption of G protein-coupled receptor kinase 2 (GRK2) resulted in a morphological defection with defective differentiation of somatic muscles and loss of fibers in both Drosophia and mouse. Furthermore, C2C12 myoblasts overexpressing a GRK2 kinase-deficient mutant generated immature myotubes, whereas GRK2 overexpression retarded the myotube differentiation. Finally, modulation of the p38MAPK pathway might contribute to a balanced GRK2 function in regulating skeletal muscle myogenesis. Given that the brain might be the most complicated part of the body, much attention has been attracted to unraveling previously unknown molecules or signaling events involved in brain development. In this issue, Dr Fan and Xu’s groups report their recent finding that TGF-b-activated kinase 1 (TAK1) is expressed in the axons of the mouse brain and can be activated by TGF-b. The activated TAK1 plays an important role in axonal growth during brain development, since TAK1 defect leads to delayed axon specification and outgrowth in brain-specific TAK1 knockout mice.
References Liu, Q.-C., Zha, X.-H., Faralli, H., et al. (2012). Comparative expression profiling identifies differential roles for Myogenin and p38a MAPK signaling in myogenesis. J. Mol. Cell Biol. 4, 386 – 397. Neguembor, M.V., Xynos, A., Onorati, M.C., et al. (2013). FSHD muscular dystrophy region gene 1 binds Suv4 – 20h1 histone methyltransferase and impairs myogenesis. J. Mol. Cell Biol. 5, 294 –307. Wu, J. (2013). Understanding and manipulating developmental complexity. J. Mol. Cell Biol. 5, 283.
# The Author (2014). Published by Oxford University Press on behalf of Journal of Molecular Cell Biology, IBCB, SIBS, CAS. All rights reserved.
Downloaded from http://jmcb.oxfordjournals.org/ by guest on April 16, 2015
Editor-in-Chief Jiarui Wu
papers on the complexity of various biological behaviors were published by Cell to celebrate its 40th anniversary. The developmental process must be one of the most complex events in multi-cellular organisms. JMCB has published several research papers in the previous Collection ‘Understanding and Mani-pulating Developmental Complexity’ (Wu, 2013). This issue publishes more articles focusing on the molecular mechanisms that regulate animal developmental processes, which should provide evidences for a better understanding of the developmental complexity. Large amounts of maternal products, such as RNAs and proteins, are stored in animal eggs to support the early embryonic development. As presented in this issue, Dr Meng’s group systematically analyzed the role of maternal Eomesodermin a (Eomesa), a T-box transcription factor, in the development of zebrafish embryos. The authors showed that maternal Eomesa was required for zygotic expression of the nodal genes ndr1 and ndr2, which are crucial factors for mesendoderm induction, as well as mxtx2, a regulator of nodal gene expression. They further demonstrated that Eomesa could directly bind to the promoter or enhancer of ndr1, ndr2, and mxtx2. Their findings reveal a conserved function of maternal transcription factors in regulating nodal gene expression and mesendoderm induction in the early development of animal embryos. Sperms, as the partner of eggs, also play critical roles in sexual reproduction. Acrosomal reaction of sperms is essential for the fertilization of eggs. In this issue, Dr Tomes’ laboratory reports that the small GTPase Rab3A behaves as a dual modulator during acrosomal exocytosis, which first exchanges GDP for GTP to accomplish docking of the acrosome to the plasma membrane and then undergoes GTP hydrolysis to allow fusion pores opening between the outer acrosomal and plasma membranes.
