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==AC de clase III==
Estas AC son as máis coñecidas polos intensos estudos realizados sobre elas debido aos seus importantes papeis na saúde humana. Tamén se encontran nalgunhas bacterias, notablemente en ''[[Mycobacterium tuberculosis]]'', na cal parecen ter un papel clave na súa patoxénese. A maioría das AC-III son proteínas de membrana integrais implicadas na [[transdución de sinais]] extracelular a respostas intracelulares. O funcionamento xeral das adenilato ciclases é o seguinte: As adenilato ciclases son a miúdo activadas ou inhibidas por proteínas G, que están acopladas a receptores de memnbrana e así poden responder aos estímulos hormonais. Cando se activa a adenilato ciclase, prodúcese AMP cíclico, que funciona como [[segundo mensaxeiro]] (o primeiro é a hormona), que interacciona e regula a outras proteínas como a [[proteína quinase A]] e os [[canal HCN|canais iónicos de apertura regulada por nucleótidos cíclicos]].
These AC's are the most familiar based on extensive study due to their important roles in human health. They are also found in some bacteria, notably ''Mycobacterium tuberculosis'' where they appear to have a key role in pathogenesis. Most AC-III's are integral membrane proteins involved in transducing extracellular signals into intracellular responses. A Nobel Prize was awarded to Earl Sutherland in 1971 for discovering the key role of AC-III in human liver, where adrenaline indirectly stimulates AC to mobilize stored energy in the "fight or flight" response. The effect of adrenaline is via a [[G protein]] signaling cascade, which transmits chemical signals from outside the cell across the membrane to the inside of the cell ([[cytoplasm]]). The outside signal (in this case, adrenaline) binds to a receptor, which transmits a signal to the G protein, which transmits a signal to adenylate cyclase, which transmits a signal by converting [[adenosine triphosphate]] to [[cyclic adenosine monophosphate]] (cAMP). cAMP is known as a [[second messenger]].<ref name="Campbell">{{cite book | author = Reece J, Campbell N | title = Biology | publisher = Benjamin Cummings | location = San Francisco | year = 2002 | pages = 207 | isbn = 0-8053-6624-5 }}</ref>
Concedéuselle o [[premio Nobel]] a Earl Sutherland en 1971 polo descubrimento do papel clave da AC-III no fígado humano, onde a [[adrenalina]] estimula indirectamente a AC para que se mobilice a enerxía almacenada na resposta de "loita ou fuxida". O efecto da adrenalina exércese por medio da fervenza de sinalización da [[proteína G]], a cal transmite sinais químicos desde fóra da célula a través da membrana ata o interior da célula ([[citoplasma]]). O sinal externo (neste caso, a adrenalina) únese a un receptor, o csl transmite un sinal á proteína G, que á súa vez transmite un sinal á adenilato ciclase, e esta converte o [[adenosina trifosfato|ATP]] en [[adenosina monofosfato cíclica|AMPc]]. O AMPc funciona como o que se chama un segundo mensaxeiro.<ref name="Campbell">{{cite book | author = Reece J, Campbell N | title = Biology | publisher = Benjamin Cummings | location = San Francisco | year = 2002 | pages = 207 | isbn = 0-8053-6624-5 }}</ref>
cAMP (cyclic adenosine monophosphate) is an important molecule in [[eukaryote|eukaryotic]] [[signal transduction]], a so-called [[second messenger]]. Adenylate cyclases are often activated or inhibited by [[G protein]]s, which are coupled to membrane receptors and thus can respond to hormonal or other stimuli. Following activation of adenylate cyclase, the resulting cAMP acts as a second messenger by interacting with and regulating other proteins such as [[protein kinase A]] and [[HCN channel|cyclic nucleotide-gated ion channels]].
PhotoactivatableDescubriuse adenylateunha cyclaseadenilato ciclase fotoactivable (PAC) was discovered inen ''E.[[Euglena gracilis]]'', andque canpode beexpresarse expressednoutros inorganismos otherpor organismsmedio throughde geneticmanipulacións manipulationxenéticas. ShiningAo blueiluminarmos lightunha on acélula cellque containingconteña PAC activatescon itluz andazul, abruptlyeste increasesencima theactívase ratee ofincrementa conversionbruscamente ofa velocidade de conversión do ATP toen cAMPAMPc. ThisEsta isé aunha usefultécnica techniqueútil forpara researchersos ininvestigadores neuroscienceen becauseneurociencia itporque allowslles thempermite toque quicklyse increaseincremente theos intracellularniveis cAMPintracelulares levelsde inAMPc en particulardeterminadas neurons[[neurona]]s, ande topara studyestudar theo effectefecto ofdese thatincremento increasena inactividae neural activityno oncomportamento thedo behavior of the organismorganismo. ForPor exampleexemplo, PACa expressionexpresión inda certainPAC neuronsen hascertas beenneuronas shownaltera too altercomportamento thede groomingaseo behaviordas inmoscas fruitda fliesfroita exposedexpostas toá blueluz lightazul.<ref name="pmid17128267">{{cite journal | author = Schröder-Lang S, Schwärzel M, Seifert R, Strünker T, Kateriya S, Looser J, Watanabe M, Kaupp UB, Hegemann P, Nagel G | title = Fast manipulation of cellular cAMP level by light in vivo | journal = Nat. Methods | volume = 4 | issue = 1 | pages = 39–42 |date=January 2007| pmid = 17128267 | doi = 10.1038/nmeth975 }}</ref> [[Channelrhodopsin-2]] is also used in a similar fashion.
===Estrutura das AC-III===
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