Insulin the simplest unicellular eukaryotes. Apart from animals, insulin-like proteins are also known to exist in the Fungi and Protista kingdoms. Insulin is produced by beta cells of the pancreatic islets in most vertebrates and by the Brockmann body in some teleost fish. Cone snails "Conus geographus" and "Conus tulipa", venomous sea snails that hunt small fish, use modified forms of insulin in their venom cocktails. The insulin toxin, closer in structure to fishes' than to snails' native insulin, slows down the prey fishes by lowering their blood glucose levels. The preproinsulin precursor of insulin is encoded by the "INS" gene.
Insulin glargine help offer moderate control of serum glucose levels. In the absence of endogenous insulin—type 1 diabetes, depleted type 2 (in some cases) or latent autoimmune diabetes of adults in late stage—insulin glargine needs the support of fast acting insulin taken with food to reduce the effect of prandially derived glucose (from food). The long-acting insulin class, which includes insulin glargine, do not appear much better than neutral protamine Hagedorn (NPH) insulin but have a significantly greater cost making them, as of 2010, not cost effective for the treatment of type 2 diabetes. It is unclear if there is a difference