Scientists at the Genome Institute of Singapore (GIS) have generated significant single-cell expression data crucial for a detailed molecular understanding of the mammalian pre-implantation period.
The pre-implantation period is a process that begins with fertilisation and ends with embryo implantation.
The knowledge gained has a direct impact on clinical applications in the areas of regenerative medicine and assisted reproduction.
This study, published in 'Developmental Cell' on 20 April 2010 is said to be the first of its kind to apply single-cell gene expression analysis of many genes to hundreds of cells in a developmental system.
Using the Fluidigm Biomark microfluidic technology and the mouse pre-implantation embryo as a model, the scientists were able to study the expression of 48 genes from individual cells and applied this to analyse more than 600 individual cells from the one-cell to 64-cell stage of pre-implantation development.
This high-throughput single-cell research methodology provides the scientists with the ability to detect dynamic patterns in cellular behaviour.
The findings of the study resolves some of the arguments pertaining to cellular differentiation events and places fibroblast growth factor signalling as the primary event in the later cell fate decisions.
Prof Edison Liu, executive director at the GIS, a biomedical research institute of the Agency for Science, Technology and Research (ASTAR), said: 'This work by Guoji Guo, Mikael Huss, Paul Robson and colleagues uses microgenomic technologies to map, over time, how a single cell decides to permanently became different parts of an embryo.
'Within one division, cells commit to specific developmental lineages by expressing defined sets of genes.
'This research now opens the possibility of assessing the genetic triggers for fate determination of individual cells in developmental time.
'On another level, this work highlights the importance of microtechnologies in advancing the understanding of early embryonic events,' he added.
Prof Davor Solter, senior principal investigator of the Institute of Medical Biology, ASTAR, said: 'The authors investigated changes in expression of multiple genes on the single-cell level during pre-implantation mouse development.
'They clearly demonstrated gradual and stochastic lineage allocation and absence of predetermination,' he added.
It is clear that individual cells and small groups of cells behave differently than the aggregate population, and these differences are key to understanding the biology of the system as a whole.
The pre-implantation period involves the first cellular differentiation events in mammalian development including the formation of pluripotent cell from where embryonic cells are derived.
Being one of the simplest mammalian developmental systems to study, it can provide comprehensive understanding of the complex molecular control of reprogramming and cell fate decisions.
