👉 Spalding's, also known as the "spindle," is a type of protein that plays a crucial role in cell division and is essential for the proper functioning of most mammalian cells. It consists of two subunits, one being a nuclear envelope protein called the nuclear pore complex (NPC) and the other being the spindle protein. These proteins are involved in the assembly of the nuclear envelope, which helps to maintain the integrity of the cell's membrane during mitosis.