Ablomin
Encyclopedia
Ablomin is a toxin
present in the venom of the Japanese Mamushi snake, which blocks L-type voltage-gated calcium channels.
snake, Gloydius blomhoffi. The term ‘ablomin’ is an acronym derived from Agkistrodon
blomhoffi, an old name for this snake.
family.
(CRISP) family. CRISPs comprise a particular group of snake venom proteins distributed among the venom of several families of snakes, such as elapids, colubrids and vipers
.
The protein exists of 240 amino acids, coded by an mRNA of 1336 base pairs. Structurally, it is composed of three distinct regions: an N-terminal protein domain, a hinge region and a C-terminal cystein-rich domain. It has a molecular mass
of 25 kDa
.
Ablomin shows great sequence homology
with triflin
(83.7%) and latisemin
(61.5%), two other snake venom components of the CRISP family, which also target voltage-dependent calcium channels. In addition, it shows partial homology with helothermine (52.8%), a venom protein of the Mexican beaded lizard; this protein, however, targets other ion channels than ablomin.
s (CNGA1
) channels.
Toxin
A toxin is a poisonous substance produced within living cells or organisms; man-made substances created by artificial processes are thus excluded...
present in the venom of the Japanese Mamushi snake, which blocks L-type voltage-gated calcium channels.
Etymology
The protein ablomin is a component of the venom of the Japanese MamushiMamushi
Gloydius blomhoffii, commonly known as the mamushi, or Japanese mamushi, is a venomous pitviper species found in China, Japan, and Korea. There are four subspecies including the nominate subspecies described here....
snake, Gloydius blomhoffi. The term ‘ablomin’ is an acronym derived from Agkistrodon
Agkistrodon
Agkistrodon is a genus of venomous pit vipers found in North America from the United States south to northern Costa Rica. The name is derived from the Greek words ἄγκιστρον 'fishhook' and ὁδοὐς 'tooth', and is likely a reference to the fangs...
blomhoffi, an old name for this snake.
Source
The protein can be found in the venom of the Japanese Mamushi snake, a member of the ViperidaeViperidae
The Viperidae are a family of venomous snakes found all over the world, except in Antarctica, Australia, Ireland, Madagascar, Hawaii, various other isolated islands, and above the Arctic Circle. All have relatively long, hinged fangs that permit deep penetration and injection of venom. Four...
family.
Chemistry
Ablomin is part of the Cystein-Rich Secretory ProteinCysteine-rich secretory protein
Cysteine-rich secretory proteins, often abbreviated as CRISPs, are a group of glycoproteins found exclusively in vertebrates. They are a subgroup of the CRISP, antigen 5 and Pr-1 protein superfamily and are substantially implicated in the functioning of the mammalian reproductive system...
(CRISP) family. CRISPs comprise a particular group of snake venom proteins distributed among the venom of several families of snakes, such as elapids, colubrids and vipers
Viperidae
The Viperidae are a family of venomous snakes found all over the world, except in Antarctica, Australia, Ireland, Madagascar, Hawaii, various other isolated islands, and above the Arctic Circle. All have relatively long, hinged fangs that permit deep penetration and injection of venom. Four...
.
The protein exists of 240 amino acids, coded by an mRNA of 1336 base pairs. Structurally, it is composed of three distinct regions: an N-terminal protein domain, a hinge region and a C-terminal cystein-rich domain. It has a molecular mass
Molecular mass
The molecular mass of a substance is the mass of one molecule of that substance, in unified atomic mass unit u...
of 25 kDa
KDA
KDA may refer to:* Karachi Development Authority* Kongsberg Defence & Aerospace* Kotelawala Defence Academy* Kramer Design Associates* Lithium diisopropylamide, KDA is the potassium analogue of lithium diisopropylamideOr kDa may refer to:...
.
Ablomin shows great sequence homology
Homology
Homology may refer to:* Homology , analogy between human beliefs, practices or artifacts owing to genetic or historical connections* Homology , any characteristic of biological organisms that is derived from a common ancestor....
with triflin
Triflin
Triflin is a cysteine-rich secretory protein , which is excreted by the venom gland of the Habu snake . Triflin reduces high potassium-induced smooth muscle contraction, suggesting a blocking effect on L-type calcium channels.- Source :Triflin is a toxin derived from snake venom...
(83.7%) and latisemin
Latisemin
Latisemin is a cysteine-rich secretory protein that can be isolated from the venom of the Black-banded sea krait, a sea snake indigineous to the warmer waters of the western Pacific Ocean...
(61.5%), two other snake venom components of the CRISP family, which also target voltage-dependent calcium channels. In addition, it shows partial homology with helothermine (52.8%), a venom protein of the Mexican beaded lizard; this protein, however, targets other ion channels than ablomin.
Target
Ablomin reduces potassium-induced contraction of smooth muscles, suggesting that it blocks L-type voltage-gated calcium channels. Moreover, ablomin may slightly inhibit rod-type cyclic nucleotide-gated ion channelCyclic nucleotide-gated ion channel
Cyclic nucleotide-gated ion channels are ion channels that function in response to the binding of cyclic nucleotides. CNG channels are nonselective cation channels that are found in the membranes of various types of cells.- Discovery :...
s (CNGA1
Cyclic nucleotide-gated channel alpha 1
Cyclic nucleotide-gated channel alpha 1, also known as CNGA1, is a human gene encoding an ion channel protein.-External links:*...
) channels.
Toxicity
Ablomin affects high potassium-induced contraction of arterial smooth muscle in rat-tails in a concentration-dependent matter. Reduction of arterial smooth muscle contraction in a rat-tail results in vasodilation of the rat-tails artery, which may lead to hypothermia. Blocking other L-type voltage gated Ca2+ channels, for instance in the heart, may lead to arrhythmias and even cardiac arrest.See also
- Other snake venom proteins in the CRISP family:
- PiscivorinPiscivorinPiscivorin is a component of snake venom secreted by the Eastern Cottonmouth . It is a member of the cysteine-rich secretory protein family, which blocks voltage-dependent calcium channels.- Etymology :...
from the Eastern Cottonmouth - TriflinTriflinTriflin is a cysteine-rich secretory protein , which is excreted by the venom gland of the Habu snake . Triflin reduces high potassium-induced smooth muscle contraction, suggesting a blocking effect on L-type calcium channels.- Source :Triflin is a toxin derived from snake venom...
from the Habu snake - OphaninOphaninOphanin is a toxin found in the venom of the King Cobra , which lives throughout South East Asia. This toxin belongs to the cysteine-rich secretory protein family...
from the King Cobra - LatiseminLatiseminLatisemin is a cysteine-rich secretory protein that can be isolated from the venom of the Black-banded sea krait, a sea snake indigineous to the warmer waters of the western Pacific Ocean...
from the Erabu snake
- Piscivorin