Mapping single-cell RNA sequencing (scRNAseq) data to tissue of origin using in situ hybridization
Daniel Fürth
Meletis Lab
ISH course
11th March 2016
daniel.furth@ki.se
Pollak Dorocic et al. 2014
Reconstructing brain from sectioned tissue
similar to...
works with...
NATURE BIOTECHNOLOGY | COMPUTATIONAL BIOLOGY | ANALYSIS
Kaia Achim, Jean-Baptiste Pettit, Luis R Saraiva, Daria Gavriouchkina, Tomas Larsson, Detlev Arendt & John C Marioni
Allen Brain Reference Atlas
Anatomic Gene Expression Atlas
Lydia Ng, et al. (2009) Nat. Neuro.
http://mouse.brain-map.org/agea
Allen Brain Reference Atlas
324 cells from cortico-striatal section
Our approach
Our approach
Comparison of Antibody-Based and DNA-Based Amplification
Allen Brain Reference Atlas
Connectivity average template (Ng et al. 2014)
Allen Brain Reference Atlas
Connectivity average template (Ng et al. 2014)
Can be used to segment processes and their direction.
Do we really have a 'BigData' problem in neuroscience?
http://www.parallac.org/
10 computers (146 processors)
Up to 64 cores per processor!
Freeman et al. (2014) Nature Methods
xx <- faithful$eruptions
fit <- density(xx)
plot(fit)
#Line 1: loading
xx <- faithful$eruptions
#Line 2: estimate density
fit1 <- density(xx)
#Line 2: draw 10'000 bootstraps
fit2 <- replicate(10000, {
x <- sample(xx,replace=TRUE);
density(x, from=min(fit1$x), to=max(fit1$x))$y
})
#Line 3: compute 95% error "bars"
fit3 <- apply(fit2, 1, quantile,c(0.025,0.975))
#Line 4: plot the estimate
plot(fit1, ylim=range(fit3))
#Line 5: add estimation error as shaded region
polygon(c(fit1$x,rev(fit1$x)), c(fit3[1,], rev(fit3[2,])), col=’grey’, border=F)
#Line 6: add the line again since the polygon overshadows it.
lines(fit1)
What other language can do this in 6 lines of code?
# install.packages('foreach'); install.packages('doSNOW')
library(foreach)
library(doSNOW)
cl <- makeCluster(2, type = "SOCK")
registerDoSNOW(cl)
getDoParName()
#matrix operators
x <- foreach(i=1:8, .combine='rbind', .packages='wholebrain' ) %:%
foreach(j=1:2, .combine='c', .packages='wholebrain' ) %dopar% {
l <- runif(1, i, 100)
i + j + l
}
#include <string>
#include <iostream>
#include <thread>
using namespace std;
//The functions we want to make the thread run.
void task1(string msg)
{
cout << "task1 says: " << msg;
}
void task2(string msg)
{
cout << "task1 says: " << msg;
}
//Main loop.
int main()
{
thread t1(task1, "Task 1 executed");
thread t2(task2, "Task 1 executed");
t1.join();
t2.join();
}
Rcpp
#include <string>
#include <iostream>
#include <thread>
using namespace std;
//The functions we want to make the thread run.
void task1(string msg)
{
cout << "task1 says: " << msg;
}
void task2(string msg)
{
cout << "task1 says: " << msg;
}
//Main loop.
int main()
{
thread t1(task1, "Task 1 executed");
thread t2(task2, "Task 1 executed");
//let main wait for t1 and t2 to finish.
t1.join();
t2.join();
}
Rcpp
Dual core
Gene specificity
about ~24'000 genes expressed in the brain.