MRC Laboratory of Molecular Biology
One of the world's leading research institutes, our scientists are working to advance understanding of biological processes at the molecular level - providing the knowledge needed to solve key problems in human health.
The spliceosome is a molecular machine that plays an important role in gene expression. It cuts non-coding sequences (introns) out of messenger RNA (mRNA) precursors, and stitches together the useful coding sequences (exons). The spliceosome performs this in two steps. First, the start of an intron is recognised, cut, and joined to a specific point in the middle of that intron, forming a lasso-like looped structure.
Internal body clocks, which time the length of a day in almost all organisms, control many aspects of human physiology and activity, from when we go to bed to when we perform best mentally and physically. Most importantly, these biological circadian clocks are in every single individual cell of our bodies, not just in the brain.
Parkinson’s disease (PD) is a neurodegenerative condition caused by the loss of dopaminergic neurons in the midbrain, which manifests clinically in the form of characteristic motor defects. Most PD cases are sporadic and found in people above the age of 60. However, roughly 10% of PD cases are autosomal recessive juvenile forms (AR-JP), causing early-onset PD. It is known that mutations in PARK genes are responsible for this, but often a molecular explanation is lacking.
Inside our cells there are many distinct membrane compartments – organelles – which carry out the different tasks that allow the cell to function. Each organelle is like a factory that requires a constant supply of raw materials to stay active. Small transport vesicles deliver this cargo of particular proteins and lipids to each organelle.
Genes are encoded in DNA and need to be copied into an intermediate mRNA molecule that contains the instructions to allow synthesis of protein. Almost every mRNA has a repetitive sequence at one end called a poly(A) tail. The length of this tail specifies the amount of time that the mRNA is present in the cell, and how often it is translated into protein. Errors or changes in the tail are found in human diseases including β-thalassemia, thrombophilia and cancer, as well as viral infections.
The connectome of an animal is the comprehensive map, or wiring diagram, of all the neural connections in the brain. However, an important challenge is how to make sense of this information. The nematode worm Caenorhabditis elegans, still the only animal for which the entire connectome has been described, illustrates the problem. Although it has only 302 neurons, these make thousands of connections.