The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: Work in the laboratory of LE is funded by the BBSRC [BB/J00815X/1] and the R.S. Macdonald Charitable Trust. Research in the laboratory of EH is funded by grants from the Regional Government [Prometeo2012-005], the Spanish Ministry of Economy and Competitiveness [BFU2010-16563] and the European Research Council [ERC2011-StG20101109]. ; Peer reviewed ; Publisher PDF
10 páginas, 5 figuras. ; [Background] The neural retina is a highly structured tissue of the central nervous system that is formed by seven different cell types that are arranged in layers. Despite much effort, the genetic mechanisms that underlie retinal development are still poorly understood. In recent years, largescale genomic analyses have identified candidate genes that may play a role in retinal neurogenesis, axon guidance and other key processes during the development of the visual system. Thus, new and rapid techniques are now required to carry out high-throughput analyses of all these candidate genes in mammals. Gene delivery techniques have been described to express exogenous proteins in the retina of newborn mice but these approaches do not efficiently introduce genes into the only retinal cell type that transmits visual information to the brain, the retinal ganglion cells (RGCs). ; [Results] Here we show that RGCs can be targeted for gene expression by in utero electroporation of the eye of mouse embryos. Accordingly, using this technique we have monitored the morphology of electroporated RGCs expressing reporter genes at different developmental stages, as well as their projection to higher visual targets. ; [Conclusion] Our method to deliver ectopic genes into mouse embryonic retinas enables us to follow the course of the entire retinofugal pathway by visualizing RGC bodies and axons. Thus, this technique will permit to perform functional studies in vivo focusing on neurogenesis, axon guidance, axon projection patterning or neural connectivity in mammals. ; This work was supported by grants to E. H. from Human Frontiers Science Program (CDA-0023) and from the Spanish Government (BFU-2004-0058). E.H. is a Ramón y Cajal Investigator from the Consejo Superior de Investigaciones Científicas (CSIC). ; Peer reviewed
Axons of retinal ganglion cells (RGCs) make a divergent choice at the optic chiasm to cross or avoid the midline in order to project to ipsilateral and contralateral targets, thereby establishing the binocular visual pathway. The zinc-finger transcription factor Zic2 and a member of the Eph family of receptor tyrosine kinases, EphB1, are both essential for proper development of the ipsilateral projection at the mammalian optic chiasm midline. Here, we demonstrate in mouse by functional experiments in vivo that Zic2 is not only required but is also sufficient to change the trajectory of RGC axons from crossed to uncrossed. In addition, our results reveal that this transcription factor regulates the expression of EphB1 in RGCs and also suggest the existence of an additional EphB1-independent pathway controlled by Zic2 that contributes to retinal axon divergence at the midline. ; Research in the laboratory of E.H. is funded by grants from the Spanish Ministry of Education and Science (BFU2004-558, BFU2007-61831), CONSOLIDER-Ingenio 2010 Program (CDS2007-023), the Regional Government of 'Generalitat Valenciana', and a CDA from the Human Frontiers Science Program. Research in the laboratory of C.M. is funded by R01 EY12736 and EY01529 grants from the NIH. ; Peer Reviewed
We thank D Baeza and M Herrera for mouse breeding, genotyping and help in in utero electroporation experiments and E Llorens and J Mullet for technical help in experiments involving ferrets. We also thank A Barco for discussion and comments on the manuscript. The laboratory of EH is funded with the following grants: (BFU2016-77605 from the National Grant Research Program, PROMETEO Program (2016/026) from Generalitat Valenciana, (PCIN2015-192-C02-02 from ERA-Net Program) and (ERC282329 from the European Research Council). Work in the laboratory of LMM and SS was supported by the National Grant Research Program (Grant BFU2014-58776-r), cofinanced by the European Regional Development Fund (ERDF). VMB holds a postdoctoral contract from the Regional Government. AJV is the recipient of a FPI fellowship from the National Grant Research Program. We also acknowledge the financial support received from the "Severo Ochoa" Program for Centers of Excellence in R&D (SEV-2013-0317). AK was supported by the Canadian Institutes for Health Research Operating Grants MOP-77556 and MOP-97758, as well as Brain Canada, Canadian Foundation for Innovation, and the W. Garfield Weston Foundation. ; Peer reviewed ; Publisher PDF
The human Alzheimer's disease (AD) brain accumulates angiogenic markers but paradoxically, the cerebral microvasculature is reduced around Aß plaques. Here we demonstrate that angiogenesis is started near Aß plaques in both AD mouse models and human AD samples. However, endothelial cells express the molecular signature of non-productive angiogenesis (NPA) and accumulate, around Aß plaques, a tip cell marker and IB4 reactive vascular anomalies with reduced NOTCH activity. Notably, NPA induction by endothelial loss of presenilin, whose mutations cause familial AD and which activity has been shown to decrease with age, produced a similar vascular phenotype in the absence of Aß pathology. We also show that Aß plaque-associated NPA locally disassembles blood vessels, leaving behind vascular scars, and that microglial phagocytosis contributes to the local loss of endothelial cells. These results define the role of NPA and microglia in local blood vessel disassembly and highlight the vascular component of presenilin loss of function in AD. ; A.E.R.-N. was the recipient of a JdlC-F fellowship from the Spanish Ministry of Economy, Industry, and Competitiveness (MINEICO) (FJCI-2015-23708), M.I.A.-V., N.L.-U., and C.O.-d.S.L. were the recipient of an FPU fellowship from Spanish Ministry of Education, Culture, and Sport (respectively, FPU15/02898, FPU14-02115, and AP2010‐1598), and R.M.-D. was the recipient of a "Sara Borrell" fellowship from ISCIII (CD09/0007). Work was supported by grants to A.P. by the Spanish MINEICO, ISCIII, and FEDER (SAF2012‐33816, SAF2015‐64111‐R, RTI2018-096629-B-100, SAF2017-90794-REDT, and PIE13/0004), by the regional Government of Andalusia ("Proyectos de Excelencia", P12‐CTS‐2138 and P12‐CTS‐2232) co-funded by CEC and FEDER funds, and by the "Ayuda de Biomedicina 2018", Fundación Domingo Martínez; J.Vitorica: Instituto de Salud Carlos III (ISCiii) of Spain, co-financed by FEDER funds from European Union (PI18/01556) by La Marató-TV3 Foundation grant 20141431; by CIBERNED (CB06/05/0094); and by Junta de Andalucia Consejería de Economía y Conocimiento through grant US-1262734; A.G.: Instituto de Salud Carlos III (ISCiii) of Spain, co-financed by FEDER funds from European Union, through grant PI18/01557; and by Junta de Andalucia Consejería de Economía y Conocimiento through grants UMA18-FEDERJA-211 and P18-RT-2233 co-financed by Programa Operativo FEDER 2014-2020. ; Peer reviewed