Mice
The mouse in the center photo shows aging-associated skin wrinkles and hair loss after two months of mitochondrial DNA depletion. That same mouse, right, shows reversal of wrinkles and hair loss one month later, after mitochondrial DNA replication was resumed. The mouse on the left is a normal control, for comparison. UAB

A group of scientists at the California Institute of Technology and the Allen Institute for Brain Science in Seattle has discovered the distinction between a mouse and a mice's brain. Apparently, the research shows that both animal's minds differ on a cellular level.

The team analyzed a region in the hypothalamus called the ventrolateral subdivision of the ventromedial hypothalamus (VMHvl) in both female and male mice. The results show that there are differences in the mammalian's brains at its cellular structure.

According to the researchers, there are also subtle variations in gene expression. Moreover, David Anderson, a senior researcher at Caltech, said that their "functional significance remains to be explained."

The hypothalamus regions where the cells were discovered control the aggression and mating behaviors in mice. The collaborative research also examined the gene expression in individual cells in the VMHvl with advanced transcriptomic techniques.

The procedure completely identifies a full set of RNA transcripts produced by the genome. It's also being used to classify different types of cells.

The researchers also observed that there are 17 distinct cell types in this tiny region of the brain. The different brain cells were compared with the help of glowing genetic tags in a method called "fluoro in-situ hybridization."

In the breakthrough discovery, the team also identified sex-specific neurons existing in the brains of male and female mice. It hadn't been seen earlier in mammals, especially the vivid differentiation between the neuron types in the case of the analyzed female and male brains.

The researchers said that they are planning on conducting further study to uncover the functions of these different cell types. The findings were published initially by Science Daily. The journal reference is named as the "Multimodal Analysis of Cell Types in a Hypothalamic Node Controlling Social Behavior."