Lamins are the major components of the nuclear lamina, a proteinaceous scaffold that provides essential structural support to the nuclear envelope. Despite its key role, little is known about the organisation of the nuclear lamina in situ because it is so technically challenging to visualise. On page 215, Reimer Stick and colleagues use field-emission scanning electron microscopy (feSEM) to re-examine the nuclear lamina in Xenopus oocytes. The authors show that the lamina is arranged into unidirectional parallel filaments that are interconnected at regular intervals, updating a previous description of the oocyte lamina as a bidirectional mesh of two sets of parallel filaments. The authors go on to express exogenous A- and B-type lamins within oocytes, and show that the two isoforms form filaments that have distinctly different structures and mechanical properties. These results hint at the potential diversity of nuclear lamina structure among cell types and organisms.
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