Upright confocal laser scanning microscope

• Subject Area: Plant Sciences
• Term: Funded in 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 565004141

Research groups at COS study the development, physiology and evolution of complex organ-isms. For many groups microscopy is one of the central approaches and, therefore, we have developed a shared and physically integrated infrastructure to address these needs. Here we apply to acquire a versatile upright confocal microscope, which will replace a similar instru-ment, which has reached the end of its productive life span after 12 years of heavy usage. The new microscope will feature medium magnification, high resolution and large working dis-tance water dipping lenses, that offer a large field of view and allow specimen to be observed with or without cover slip. In addition, the system will feature a multi laser setup to allow simul-taneous imaging of markers from the blue to the red ends of the spectrum, as well as a spec-tral detector to minimize channel crossover and minimize background. This configuration has proven ideal for all applications that require imaging of larger specimen in submerged conditions. These include live shoot and root apical meristems, or thick stem sections of Arabidopsis thaliana, Nicotiana benthamiana leaves, or Zebrafish embryos. Typical projects that rely on the availability of the new instrument include the study of regulato-ry mechanisms underlying plant stem cell homeostasis and tissue development in Arabidopsis shoot and root meristems. Since the stem cell population itself, as well as the cells providing the organizational cues for meristem integrity, undergo permanent turnover, multi-spectral and time-resolved live imaging is a key technique for these studies. The Lohmann lab has devel-oped a wide portfolio of genetically encoded cell identity and signalling markers along with computational analysis approaches to resolve these complex interactions. The second im-portant project that will make use of the new instrument focuses on signalling systems in the vascular cambium of Arabidopsis. The Greb lab has a particular interest in the role calcium as a signalling integrator and successfully implemented live imaging using genetically encoded markers. Since calcium signalling is sensitive to wounding, thin sections of the stem do not lend themselves for these analyses. Instead, imaging of submerged thick sections on an up-right confocal without coverslip has turned out to be ideal to record calcium signalling signa-tures in the cambium. A third example project the new instrument will serve is the analysis of Zebrafish embryo development using genetically encoded and expressed barcodes along with fluorescent markers. The Saunders lab has developed a high-resolution expression atlas of zebrafish development and will now bring together lineage tracing based on RNAseq and imaging to resolve the origin and function of diverse neural crest cell populations. To achieve this ambitious goal the Saunders lab needs access to an upright confocal with large field of view that allows repeated live imaging of Zebrafish embryos.

• DFG Programme: Major Research Instrumentation
• Major Instrumentation: Aufrechtes konfokales Laserscanning Mikroskop
• Instrumentation Group: 5090 Spezialmikroskope
• Applicant Institution: Ruprecht-Karls-Universität Heidelberg
• Leader: Professor Dr. Jan Lohmann