Squamous cells are a type of epithelial cell, and they don't produce a single, defining protein. Instead, they express a variety of proteins that are crucial for their function, which is primarily to form a protective barrier.

Here are some important proteins found in squamous cells:

* Keratin: A fibrous protein that provides structural support and protection, particularly in skin and hair.

* Cytokeratins: A family of intermediate filament proteins that are specific to epithelial cells, including squamous cells. They contribute to cell shape and adhesion.

* Desmosomal proteins: These proteins form cell-cell junctions, helping to bind squamous cells together and maintain the integrity of epithelial tissues.

* Tight junction proteins: These proteins create a seal between cells, preventing leakage and maintaining the barrier function of squamous cells.

* Cadherins: Cell adhesion molecules that contribute to cell-cell interactions and tissue organization.

* Integrins: Proteins that connect the cytoskeleton to the extracellular matrix, contributing to cell adhesion and signaling.

The specific proteins expressed by a squamous cell can vary depending on its location and function. For example, squamous cells in the skin will have a different protein profile than those in the lining of the mouth.