RESUMO
Phospholipase A2 inhibitors (PLIs) are glycoproteins secreted by snake liver into the circulating blood aiming the self-protection against toxic venom phospholipases A2. In the present study, we describe the first complete nucleotide sequence of a bPLI from venom glands of a NewWorld snake, Lachesis muta. The deduced primary structure was compared to other known bPLIs and recent literature findings of other possible roles of PLIs in snakesare discussed.
Assuntos
Lachesis muta/classificação , Lachesis muta/intoxicação , /antagonistas & inibidores , Serpentes/classificação , Serpentes/fisiologia , Venenos de Serpentes/síntese química , Venenos de Serpentes/toxicidade , /análiseRESUMO
Phospholipase A(2) inhibitors (PLIs) are glycoproteins secreted by snake liver into the circulating blood aiming the self-protection against toxic venom phospholipases A(2). In the present study, we describe the first complete nucleotide sequence of a ßPLI from venom glands of a New World snake, Lachesis muta. The deduced primary structure was compared to other known ßPLIs and recent literature findings of other possible roles of PLIs in snakes are discussed.
Assuntos
Bothrops/metabolismo , Venenos de Crotalídeos/metabolismo , Glândulas Exócrinas/metabolismo , Fosfolipases A2 do Grupo IV/antagonistas & inibidores , Sequência de Aminoácidos , Animais , Sequência de Bases , Eletroforese em Gel de Ágar , Inibidores Enzimáticos , Fosfolipases A2 do Grupo IV/química , Fosfolipases A2 do Grupo IV/genética , Dados de Sequência MolecularRESUMO
Phoneutria spider venoms are a rich source of bioactive components. The limited amounts of crude material available, however, can be considered as a major hindrance for a faster development in the field. In the present study, we attempted to establish primary cultures of venom glands of Phoneutria nigriventer as an alternative, in vitro source of venom. Three different developmental stages were tried as starting materials: whole embryo (inside the cocoon), nymph (early after cocoon hatching) and young adult (1 year after cocoon hatching). The embryonic cells remained in suspension in the primary cultures, with no signs of adhesion or differentiation, for about 6 months. Nevertheless, this culture was useful for the first chromosome C-banding of Phoneutria. An average of 29+/-1 acrocentric chromosomes were found. Striated muscle cells were the only kind of cells in the culture of venom glands from Phoneutria nymphs. The most promising results were achieved with 1-year-old specimens. Besides muscle, adherent epithelial cells were also obtained in culture. Although these cells remained in culture for a short time (up to 48 h) immunochemical analysis of the culture supernatant evidenced the presence of Phoneutria venom components. This can be considered as a first step toward the functional cultures of venom glands of Phoneutria spiders.
