A Wrinkle In Time
A developing fruit fly embryo, one of the workhorse organisms of developmental genetics, captured in four dimensions using an amazing new microscopy technique called lightsheet fluorescence microscopy. Fluorescent microscopy has allowed us to decipher the inner workings of biological machinery for decades, but observing those glowing labels over periods of hours or days at a time has been difficult.
A fluorescent label, the chemical beacons that give off light when excited by certain wavelengths, can only shine for so long before running out of quantum juice. This new technique uses a thin, sheet-like laser beam to gently illuminate only a thin slice of a specimen at a time, it can be used on living organisms over a period of many hours.
Computers assemble gigabytes worth of 2D images into 3D structures, and those are laced together on a timeline to make movies of cellular dynamics. The random dots in the foreground and background are reference beads to orient the images.
Now for the good stuff! Watch this fly embryo evolve before your eyes from a blobby grain of rice to a ridged worm, sculpted only by the power of overlapping chemical gradients.
(more lightsheet goodies at Cell Picture Show)