A human-derived bradeion protein, which has the following properties: (i)
it is a transmembranous protein; (ii) it has a structure characteristic
of growth hormone and cytokine receptors even in a structure of its
transmembranous portion when its structure is determined by a
hydrophobicity analysis according to Kyte-Doolittle method; (iii) it is
expressed at a high level in a human adult brain, and in less amount in
the heart, while it is not expressed in other adult organs or fetus; (iv)
it induces programmed cell death (apoptosis) when over-expressed in a
cultured human nerve cell lines; (v) it induces termination of cell
division and aging when over-expressed in a cultured human normal cell;
(vi) it is located in cytoplasm, and forms an intracellular aggregate
when overexpressed; and (vii) besides human adult neurons, it is
specifically expressed in a human colorectal cancer cell line or in a
skin cancer cell line, or an analogue thereof.