An atlas that will bring together the cellular diversity of all species on Earth

Our planet is a vast network of living cells, each with specialized functions and a unique evolutionary history that we do not yet know. Already at school we are told something about these girls; and most importantly, the cells are basic unit of life. They are its most basic form, the building blocks from which organisms are built.

Can you imagine how many of them each of us can have? The average person, for example, is approximately 37 billion; and this figure makes no sense to be compared with the figure of the blue whale. Understanding the biodiversity of all cells is not an easy task, and even so, this is the goal that has been proposed Cellular Atlas of Biodiversity.

Last May, scientists from around the world met in Barcelona to lay the foundations for this project, led by Arnau Sebe-Pedros, ICREA researcher at the Center for Genomic Regulation (CRG). They aimed to create a common space where people already involved in creating species-specific atlases could share their experiences; and the idea came up: if we’re going to do this research anyway, why not combine it and create something bigger?

What is (or rather will be) a Cellular Atlas of Biodiversity?

The cell atlas (as a whole) is map which shows and describes the different types of cells in the body; organized collection information about what cells do

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Just like a geographic atlas shows you detailed information about places, a cell atlas will give you detailed information about cells and their functions; because although Every cell in our body contains the same DNA.different cells use different parts of it, so a blood cell is not a nerve cell, and vice versa.

New ‘cellular atlases’ reveal unprecedented details of the human body

The Cellular Atlas of Biodiversity aims to achieve this goal on a large scale: mapafter study cell by cell, diversity mobile phone of all living things from the earth. In its final form it will be a large database; but this implies a whole previous process.

Arnau Sebe explains that the first thing we need is to have genomes (which become something like our instructions) sequenced, which serves to decipher genetic codes. “But in addition to linear sequences, we are interested in I know how they work genomes. We aim to determine how genes are regulated or, for example, how diversity in cell types is encoded,” explains the researcher.

“We are interested to know how do they work Genomes beyond their linear sequences”

To obtain this information, laboratories use technologies Single-cell transcriptomicswhich allow you to measure the genes expressed in each of the body’s cells (hence cell to cell). “We have these technologies, as well as genome sequencing, which has been a revolution in recent years. In that sense, it’s great!” Sebe says. But he adds: “However, we also have a number problem It’s not trivial.”

How are you going to do this with crab?

Arnau Sebe was discussing the project with another researcher when he asked him: “But how are you going to do this with a crab? How do you take a crab and dissociate its cells to study them?” It’s not about putting organisms in blenders; First, they must be alive. And the goal is not to keep a blue whale in a laboratory.

Dissociate cells to create pendants is one of the main challenges: There is no universal solution. Each type will have specific requirements for sample collection, data storage, processing and analysis. Using one method can destroy RNA in cells of another species and vice versa, resulting in inaccurate maps. Another problem is that the nature of the data collected from one species means that it cannot be compared with cell atlases of another species.

“These are boring things, but they will allow us to create, if not a universal protocol, then a kind of decision tree”

Hence Phase 0 The Atlas (the one currently funded) focuses on test and compare methodologies to solve this first part of the process. “This is a boring thing, but it will allow us to create, if not a universal protocol, then some kind of Decision tree“, says the researcher. In short, this will be a scheme that will allow scientists to know which method is the fastest and cheapest (let’s call it A), and will also allow them to know which alternative is the most logical if the first option does not work or is not possible apply directly.

The study of methodologies will be carried out in a few ten or twelve organisms differ from each other and include algae, plants and animals. The task will be carried out, in addition to Sebe, by other scientists from the universities of Oxford, Chicago and Heidelberg: Tom Richards, Heather Marlow, Jordi Solana and Lauren Saunders. This team includes bioinformatician Irene Papatheodorou from the EBI/Earlham Institute, who will work on another important task of the project: creating standardized templates for the data received, as well as their storage.

They complete the first cellular atlas of the nonhuman primate body.

“My vision of the project is that first we need to do this unpleasant business of testing methodologies, and then do medium-scale pilot projects, throw it out for everyone to see, like hook, and let the rest of the scientists start biting. Encourage the formation of a community where methods are discussed, not just results,” advocates Sebe.

Later, in Phase 1 Data will begin to be generated for hundreds of species. The researcher says the process is expected to speed up from here: “Once you get the suspension issue sorted out, which is the hardest part, you should be able to make the atlas in a week.” This data can be downloaded raw (raw) or used interactively for comparison.

Opening Recipe

The creation of a cellular atlas of biodiversity will allow Applications in various fields such as industry or pharmaceuticals. But it would also allow us to create synthetic biological systems and understand origins and evolution every form of life. But beyond these practical motives, the researcher admits that when he creates an atlas, his true motivation is the realization that he is looking where no one has seen before.

“You are always discovering something; and even if you had an intuition before, you have to be prepared to find something you didn’t expect,” he explains. I recently created the first cell atlases for Placozoans

(very simple animals, shaped like a flattened cake) and found cells similar to neurons in them; and everything indicates that ours descended from theirs.

“You are always discovering something; and even if you had an intuition before, you must be prepared to find something you didn’t expect.”

The discipline responsible for conducting these investigations is Comparative biology, and to study a process or cell, different species are used, of which there may be five, ten or a maximum of twenty. “The Cellular Atlas of Biodiversity suggests that within ten years we could see thousands and thousands of species at the same time, similar to what we are doing now with genomes,” Sebe said excitedly.

The researcher’s conclusion is that although very important discoveries have already been made in the cellular architecture of life, they were largely the result of individual efforts, and that combining these efforts could add value to their work and open the door to a higher level. unprecedented understanding of the diversity and evolution of life.