Growth differentiation factors (GDFs) are a subfamily of proteins belonging to the transforming growth factor beta superfamily that have functions predominantly in development.^[1]

Types

Several members of this subfamily have been described, and named GDF1 through GDF15.

• GDF1 is expressed chiefly in the nervous system and functions in left-right patterning and mesoderm induction during embryonic development.^[2]
• GDF2 (also known as BMP9) induces and maintains the response embryonic basal forebrain cholinergic neurons (BFCN) have to a neurotransmitter called acetylcholine, and regulates iron metabolism by increasing levels of a protein called hepcidin.^[3][4]
• GDF3 is also known as "Vg-related gene 2" (Vgr-2). Expression of GDF3 occurs in ossifying bone during embryonic development and in the thymus, spleen, bone marrow brain, and adipose tissue of adults. It has a dual nature of function; it both inhibits and induces early stages of development in embryos.^[5][6][7]
• GDF5 is expressed in the developing central nervous system, with roles in the development of joints and the skeleton, and increasing the survival of neurones that respond to a neurotransmitter called dopamine.^[8][9][10]
• GDF6 interacts with bone morphogenetic proteins to regulate ectoderm patterning, and controls eye development.^[11][12][13]
• GDF8 is now officially known as myostatin and controls the growth of muscle tissue.^[14]
• GDF9, like GDF3, lacks one cysteine relative to other members of the TGF-β superfamily. Its gene expression is limited to the ovaries, and it has a role in ovulation.^[15][16]
• GDF10 is closely related to BMP3 and has a roles in head formation and, it is presumed, in skeletal morphogenesis.^[17][18] It is also known as BMP-3b.
• GDF11 controls anterior-posterior patterning by regulating the expression of Hox genes,^[19] and regulates the number of olfactory receptor neurons occurring in the olfactory epithelium,^[20] and numbers of retinal ganglionic cells developing in the retina.^[21]
• GDF15 (also known as TGF-PL, MIC-1, PDF, PLAB, and PTGFB) has a role in regulating inflammatory and apoptotic pathways during tissue injury and certain disease processes.^[22][23][24]