利用RNA velocity来做细胞trajectory inf
【搬运】文章转自：
https://www.cnblogs.com/leezx/p/9504896.html
单细胞转录组确实是利器，但我们大多只利用了表达的信息，而从reads到表达之间的信息完全被我们忽略了。
最近nature发了一篇单细胞方法类文章，讲得就是如何利用RNA velocity来做细胞发育路径的推断。
velocyto-notebooks
首先需要了解一些基本概念：
RNA velocity：the time derivative of the gene expression state—can be
directly estimated by distinguishing between unspliced and spliced mRNAs
in common single-cell RNA sequencing protocols. a high-dimensional
vector that predicts the future state of individual cells on a timescale
of hours. 比较抽象，一开始很难理解。
half-life of mRNA：Translation in both prokaryotes and eukaryotes
involves three phases: initiation, elongation, and termination. The
relative abundance of nascent (unspliced) and mature (spliced) mRNA can
be exploited to estimate the rates of gene splicing and
degradation. could reveal the rate and direction of change of the entire
transcriptome during dynamic processes.
参考：
for mRNA Half-Life of 19 977 Genes Obtained by DNA Microarray Analysis
of Pluripotent and Differentiating Mouse Embryonic Stem Cells
Messenger RNA Half-Life Measurements in Mammalian Cells
Method:
转自 原创： 王木木 单细胞天地
