KATNA1, also known as katanin p60 ATPase-containing subunit A1, is a microtubule-cleaving enzyme. It is crucial for cytoskeletal rearrangements, which are involved in neural protrusion development, cell division, motility, and morphogenesis [1,2,3,5]. Microtubule severing is an essential process for the reorganization of microtubules based on cellular needs, such as during mitosis in dividing cells and in the formation of axons and dendrites in non-dividing neurons [4].

In male mammalian meiosis and spermiogenesis, gene knockout mouse models have shown that KATNA1 and its paralogue KATNAL1 act co-operatively. They collectively regulate the male meiotic spindle, cytokinesis, midbody abscission, and spermatid remodelling events [2]. In neurons, studies on cultured hippocampal neurons (a form of in-vitro functional study relevant to in-vivo neural function) have demonstrated that KATNA1 promotes neurite outgrowth. Mutation of the SUMOylation site K330 in KATNA1 abolishes its microtubule-severing ability and the promotion of neurite outgrowth, indicating that SUMOylation at this site is important for its function [1]. Also, the interaction between KATNA1 and CRMP3 has been shown to enhance microtubule-severing efficiency and promote hippocampal neurite outgrowth, as genetic knockout of either protein significantly inhibits neurite outgrowth [3].

In conclusion, KATNA1 is vital for microtubule-related biological processes, especially in neural development and male reproductive processes. Gene knockout models, both in the context of meiosis and neural cell function studies, have provided key insights into its functions. Understanding KATNA1's role can potentially contribute to research in neurodegenerative diseases and male infertility [1,2,3].