Overlay imagesc on binary image

Hi Matlab users:

I am trying to overlay an imagesc image on top of a binary image. I searched for it online, but no luck. Below is my code:

figure;
imshow(BW4);
hold on
imagesc(image2,'AlphaData',0.5); axis equal; axis tight; axis off;
myColorMap = jet(256);
myColorMap(1,:) = 0;
colormap(myColorMap); colorbar;
hold off

The output what I am getting looks like below image on right, instead of the jet colormap lines on top of white color. Can someone help me to fix this issue? I appreciate your time and effort.

Thanks,