Sparse-labeling Services

Introduction of Sparse-labeling

Sparse-labeling means that the labeling density is about 1% and labeled neurons do not obscure each other. It is important for visualizing synaptic structures as well as following axons or dendrites across long distances.

In neuroscience, to clarify the developmental principles and functional logic of neural circuits, it is essential to access individual neurons. There are three main strategies to realize the analysis of a single nerve cell or its precursor, including sparse-labeling, the introduction of more labels, and improved image resolution. Among them, the labeling strategy still occupies a key advantage despite the current progress in nanoscale imaging. In general, sparse-labeling can be achieved by locating labels to specific cells or distributing them in a random manner or a combination of the two. Golgi straining remains a benchmark for sparse-labeling. Sparseness and randomness are the main characteristics of sparse-labeling and they are related because the labeling probability directly affects the labeling density. The sparseness of the labeling can be controlled by adjusting the random process.

Transcriptional Strategies for Sparse-labeling

It has been proved that compared with random labeling, the use of transgenic animals expressing reporters from cell-type specific promoter fragments is more efficient for many scientific problems. Some neuron types are sufficiently sparsely distributed for single-cell analysis, but spatial clustering neurons are more typical, and subdivision of the expression pattern is required. In this case, there are two types of transcriptional strategies, including deterministic sparse transcription and stochastic sparse transcription.

Fig.1 MORF3 Mice Enable Brainwide Sparse Labeling of Microglia and Astrocytes to Reveal Their Detailed Morphology. (Veldman, 2020)

Available Markers for Sparse-labeling

• Fluorescent proteins (FPs) - directly detectable and can be restricted to specific cell types.
• Chromogenic enzymes - with higher signal amplification.
• Small epitope tags - useful in fusion proteins.
• Synthetic dyes - can be sparsely distributed with DiOlistics.
• miniSOG - a small, genetically encodable protein module.

Available Methods for Sparse-labeling

• Golgi straining
• DiOlistics method
• Dye microinjections
• Low-titer viral infections
• MORF/Cre mouse lines

Creative Biolabs is one of the well-recognized experts who are professional in applying advanced platforms for a broad range of neurosciences research. We are pleased to use our extensive experience to offer the best service and the most qualified products to satisfy each demand from our customers. If you are interested in our services and products, please do not hesitate to contact us for more detailed information.

References

1. Veldman, M.; et al. Brainwide genetic sparse cell labeling to illuminate the morphology of neurons and glia with cre-dependent MORF mice. Neuron. 2020, 108(1): 111-127. e6.
2. Jefferis, G.; et al. Sparse and combinatorial neuron labelling. Current opinion in neurobiology. 2012, 22(1): 101-110.

For Research Use Only. Not For Clinical Use.