Preprotachykinins are
precursor proteins that are modified into
tachykinin peptides
Tachykinin peptides are one of the largest families of neuropeptides, found from amphibians to mammals. They were so named due to their ability to rapidly induce contraction of gut tissue. The tachykinin family is characterized by a common C-termi ...
. Via
alternative splicing
Alternative splicing, alternative RNA splicing, or differential splicing, is an alternative RNA splicing, splicing process during gene expression that allows a single gene to produce different splice variants. For example, some exons of a gene ma ...
and
post-translational modification
In molecular biology, post-translational modification (PTM) is the covalent process of changing proteins following protein biosynthesis. PTMs may involve enzymes or occur spontaneously. Proteins are created by ribosomes, which translation (biolog ...
s, preprotachykinins produce multiple peptide
neurotransmitter
A neurotransmitter is a signaling molecule secreted by a neuron to affect another cell across a Chemical synapse, synapse. The cell receiving the signal, or target cell, may be another neuron, but could also be a gland or muscle cell.
Neurotra ...
s.
There are two human preprotachykinins:
#
preprotachykinin-1 (also PPT-1, PPT-I, or PPT-A), which produces
substance P
Substance P (SP) is an undecapeptide (a peptide composed of a chain of 11 amino acid residues) and a type of neuropeptide, belonging to the tachykinin family of neuropeptides. It acts as a neurotransmitter and a neuromodulator. Substance P ...
and
neurokinin A
Neurokinin A (NKA), formerly known as Substance K, is a neurologically active peptide translated from the pre-protachykinin gene. Neurokinin A has many excitatory effects on mammalian nervous systems and is also influential on the mammalian inflam ...
(also called "substance K"), and the derived
neuropeptide K Neuropeptide K (also known as neurokinin K), is a protein encoded by the TAC1 gene. It is an elongated derivative of the N-terminus of neurokinin A as the final post-translational processing product of beta-preprotachykinin.
Like neurokinin A, ne ...
and
neurokinin gamma.
#
preprotachykinin-2 (also PPT-2, PPT-II, or PPT-B), which produces
neurokinin B
Neurokinin B (NKB) belongs in the family of tachykinin peptides. Neurokinin B is implicated in a variety of human functions and pathways such as the secretion of gonadotropin-releasing hormone.
Additionally, NKB is associated with pregnancy in fe ...
.
References
{{Reflist
Neuropeptides
Precursor proteins