Adenylate and guanylate cyclases of cecropia silkmoth fat body.
نویسندگان
چکیده
Adenylate and guanylate cyclases were assayed in silkmoth fat body homogenates by measuring the conversion of [cc-3tP]nucleoside triphosphates to cyclic [32P]nucleotides. Adenylate cyclase was dependent on dithiothreitol, required either Mg2’ or MI?+ for activity, was activated by NaF, and inhibited by Triton X-100. Guanylate cyclase was not dependent on dithiothreitol, was strictly dependent upon Mnzf, unaffected by NaF, and activated by Triton X-100. Both cyclases had pH optima near 8.0 and were located chiefly in the particulate fraction of homogenates. Activities of both cyclases were maintained or elevated during the larval-pupal transformation and, in contrast to cyclic nucleotide phosphodiesterases, showed little decline in the early diapausing pupa.
منابع مشابه
Fat body protein granules and storage proteins in the silkmoth, Hyalophora cecropia
Fat body cells of silkmoth pupae (Hyalophora cecropia ) contain granules, showing a less dense outer zone and a denser, often crystalline, inner portion appear after cocoon spinning and increase until the larval-pupal ecdysis; more granules are formed in females than in males. Urate granules, appearing fibrous in internal structure, first form about the same time, but their accumulation is more...
متن کاملGuanylate cyclase in Dictyostelium discoideum with the topology of mammalian adenylate cyclase.
The core of adenylate and guanylate cyclases is formed by an intramolecular or intermolecular dimer of two cyclase domains arranged in an antiparallel fashion. Metazoan membrane-bound adenylate cyclases are composed of 12 transmembrane spanning regions, and two cyclase domains which function as a heterodimer and are activated by G-proteins. In contrast, membrane-bound guanylate cyclases have on...
متن کاملCrystal Structures of the Catalytic Domain of Human Soluble Guanylate Cyclase
Soluble guanylate cyclase (sGC) catalyses the synthesis of cyclic GMP in response to nitric oxide. The enzyme is a heterodimer of homologous α and β subunits, each of which is composed of multiple domains. We present here crystal structures of a heterodimer of the catalytic domains of the α and β subunits, as well as an inactive homodimer of β subunits. This first structure of a metazoan, heter...
متن کاملMycobacterium Tuberculosis Signaling via c-AMP
Adelynate cyclases (ACs), which catalyze synthesis of cAMP from ATP and yield pyrophosphate as a by-product, can be classified into four different classes according to their common features: Class I cyclases, related to enterobacterial adenylate cyclases; Class II, toxic adenylate cyclases isolated from bacterial pathogens; Class III, a large and probably ancient class that comprises cyclases f...
متن کاملRhizobium meliloti adenylate cyclase is related to eucaryotic adenylate and guanylate cyclases.
A gene from Rhizobium meliloti coding for an adenylate cyclase was sequenced, and the deduced protein sequence was compared with those of other known adenylate cyclases. No similarity could be detected with the procaryotic counterparts. However, striking similarity was found with the catalytic region of Saccharomyces cerevisiae adenylate cyclase, the cytoplasmic domains of bovine adenylate cycl...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Journal of insect physiology
دوره 22 12 شماره
صفحات -
تاریخ انتشار 1976