UCSF researchers identify molecular characteristics in the human brain developing -
UC San Francisco researchers have identified the unique characteristics of cells in the human brain development using the latest technologies for genetic analysis activity in individual cells, and demonstrated that investigations of large-scale cell can be performed once thought can much more efficiently and cheaply.
molecular characteristics "were identified in various cell types with a new strategy of the hundreds of individual cell analysis," said Arnold Kriegstein, MD, PhD, director of the Eli and Edythe broad Center of regeneration medicine and stem cell Research at UCSF. "We expect to use this approach to help us better understand how the human cortex complexity comes from cells that are spun off by cell division from stem cells in the germinal region of the brain. "
the research team focused on the technology used device" microfluidics, "in which individual cells are captured and the flow in the rooms at the nanoscale, where they undergo effectively and accurately the chemical reactions necessary for the DNA sequencing. research has shown that the number of read steps to identify and express unique sequences and identify the kinds successfully cell is 100 times less than what was assumed. The technology, developed by Fluidigm Corporation, can be used individually to treat 96 cells simultaneously.
"Routine capture individual cells and accurate sampling of their molecular characteristics is now possible," said Alex Pollen, PhD, who along with fellow Kriegstein-lab postdoctoral fellow Tomasz Nowakowski, PhD, led key experiments in which they analyzed gene activation in 301 cells throughout the human brain development Their results were published time:. August 3 in Nature Biotechnology
. Kriegstein said the identification of hundreds of new biomarkers for various types of cells will improve scientists' understanding of the emergence of specialized subtypes of neurons. in the end, the combination of this new method of focusing on gene activity in individual cells with other techniques involving single-cell microscopic imaging may reveal the origin of brain development disorders, he added.
The process could shed light on several brain disorders, including lissencephaly, in which the folds in the brain's cortex fail to develop, as well as diseases diagnosed later in development, as autism and schizophrenia, Kriegstein said.
According to the Nature study co-authors biotechnology, this analysis strategy molecules in single cells is likely to find favor not only among researchers who explore how specialized cells arise at times and specific locations within the developing organism, but also among those monitoring the characteristics of the cells in stem cells designed for tissue replacement, and those who probe the diversity of cells in tumors to identify those responsible for survival and spread of cancer cells.
Regardless of the degree of purity, in a biological sample untreated, there is a variety of cells representing various types of tissue. The researchers were sequencing the combined genetic material in these samples. To investigate which genes are active and which are dormant, they use brute repetition of sequencing steps to capture a sufficient number of messenger RNA sequences, which are transcribed from genes switched on. . However, it is difficult to conclude from mixed tissue samples whose genes are expressed in specific cell types
Pollen and Nowakowski showed that fewer steps - and less time and money - are necessary to distinguish between different types of cells by single cell analysis than had been thought.
"We are studying an ecosystem of different but related types of cells in the brain," said Pollen. "We break down the community in different populations of cells in order to understand their parts and functional components so that we can accurately predict how they will develop."
Joe Shuga, PhD, co-author on the paper and principal investigator at Fluidigm Corporation, said that the system developed by the company to capture and prepare the cells for mRNA reading sequencing yields more specific sequences regularly.
EmoticonEmoticon