NEU4

NEU3

NEU3 is a human gene that encodes the enzyme sialidase-3, which is involved in the metabolism of sialic acids. Sialic acids are a family of nine-carbon sugars that are typically found at the terminal position of glycan chains on the surfaces of cells and soluble proteins. The NEU3 enzyme specifically acts on gangliosides, which are sialic acid-containing glycosphingolipids, playing a crucial role in cellular processes such as cell signaling, differentiation, and apoptosis.

Function

NEU3 is a member of the sialidase family, which includes other sialidases such as NEU1, NEU2, and NEU4. The primary function of NEU3 is to catalyze the removal of sialic acid residues from gangliosides. This desialylation process is important for modulating the structure and function of cell membranes, influencing cell-cell interactions, and regulating signal transduction pathways.

NEU3 is predominantly localized to the plasma membrane, where it interacts with its substrates. The enzyme's activity is crucial for the regulation of ganglioside composition in the membrane, which in turn affects various cellular functions.

Clinical Significance

Alterations in NEU3 activity have been associated with several diseases. Overexpression of NEU3 has been observed in certain types of cancer, where it may contribute to tumor progression by altering cell surface glycosylation patterns and enhancing cell motility and invasion. Conversely, reduced NEU3 activity has been linked to neurodegenerative diseases, where impaired ganglioside metabolism can affect neuronal function and survival.

Research into NEU3 inhibitors and modulators is ongoing, with the aim of developing therapeutic strategies for conditions associated with dysregulated sialidase activity.

Structure

The NEU3 protein is composed of several domains that are characteristic of sialidases, including a catalytic domain that is responsible for its enzymatic activity. The structure of NEU3 has been studied using techniques such as X-ray crystallography and molecular modeling, providing insights into its substrate specificity and mechanism of action.

Expression

NEU3 is expressed in various tissues, with particularly high levels in the brain, skeletal muscle, and heart. Its expression is regulated by multiple factors, including developmental cues and environmental stimuli. The regulation of NEU3 expression is complex and involves transcriptional, post-transcriptional, and post-translational mechanisms.

Research Directions

Current research on NEU3 focuses on understanding its role in health and disease, elucidating its regulatory mechanisms, and exploring its potential as a therapeutic target. Studies are also investigating the interactions between NEU3 and other cellular components, such as glycosyltransferases and glycosidases, to better understand its function in the context of the broader glycome.

Also see

• Sialic acid
• Ganglioside
• Glycosylation
• NEU1
• NEU2
• NEU4