During fertilisation, an egg and a sperm fuse to form a new embryo. To create the egg, a precursor cell called an oocyte undergoes meiosis: a specialised form of cell division in which half the chromosomes are separated away leaving exactly the right number of chromosomes in the egg. Meiosis in human oocytes is highly […]
Insight on Research
Revealing how GPCRs activate Gα proteins.
G protein coupled receptor (GPCR) mediated signalling is one of the largest and the most diverse signalling pathways in cellular systems. Human GPCRs sense various signals and activate different Gα proteins to trigger distinct cellular responses. This signalling pathway is important for a broad range of processes such as regulation of the immune system, neurotransmission, […]
Structure of the human 20S proteasome with a ligand revealed by cryo-EM
The proteasome is a protein recycling complex that plays a critical role in the smooth running of our cells. It is present in all multicellular organisms and facilitates cell renewal and the controlled death of damaged cells. Paula da Fonseca, from the LMB’s Structural Studies Division, and Edward Morris, from the Institute of Cancer Research, […]
Spliceosome U4/U6.U5 tri-snRNP structure revealed by cryo-EM
Genes in eukaryotic organisms are frequently interrupted by non-coding segments called introns. Before the protein can be produced, the entire length of each gene including the introns, is transcribed to produce precursor messenger RNA (pre-mRNA). An immense and dynamic molecular machine known as the spliceosome then removes the introns and splices the coding segments together […]
Atomic structure of the anaphase-promoting complex (APC/C)
The anaphase-promoting complex (APC/C) is an unusually large multi-subunit complex that has a key role in cell division, controlling chromosome segregation and the cell cycle. Using electron cryo-microscopy (cryo-EM), David Barford and his group in the LMB’s Structural Studies Division have solved the first atomic structure of the APC/C, revealing its molecular architecture in unprecedented […]
Human egg defects caused by error-prone spindle assembly
Miscarriages and genetic disorders, such as Down’s syndrome, are often caused by errors when an egg develops from its progenitor cell, the oocyte. Most defects occur during meiosis, a specialised form of cell division that leads to the formation of an egg. To ensure the egg cell has exactly the right number of chromosomes, an […]