Signal Transduction PathwaysTransmi

Signal Transduction Pathways

Transmission is continued either by a series of biochemical changes within the cell or by modification of the cell membrane potential by the movement of ions in or out of the cell. Receptors that initiate biochemical changes can do so either directly via intrinsic enzymatic activities within the receptor or by activating intracellular messenger molecules.

Signal transducing receptors are of four general classes:

Receptors that penetrate the plasma membrane and have intrinsic enzymatic activity or are enzyme associated (Enzyme-linked Receptors)
Receptors that are coupled, inside the cell, to G proteins (7-TM Receptors)
Receptors that are found intracellularly and upon ligand binding directly alter gene transcription (Nuclear Receptors)
Ligand-gated ion channels

The intracellular component of signal transduction is highly receptor specific, thereby maintaining the specificity of the incoming signal inside the cell. Signal transduction pathways amplify the incoming signal by a signaling cascade using a network of enzymes that act on one another in specific ways to ultimately generate a precise and appropriate physiological response by the cell. Signal transduction involves altering the behavior of proteins in the cascade, in effect turning them on or off like a switch. Adding or removing phosphates is a fundamental mechanism for altering the shape, and therefore the behavior, of a protein. Several small molecules within the cell act as intracellular messengers (also known as second messengers). These include cAMP, cGMP, nitric oxide, lipids and Ca2+ ions. Activated receptors stimulate second messenger production, which in turn activate other enzymes and so the cascade continues.

Hasil (Bahasa Indonesia) 1:

TRANSDUKSITransmisi dilanjutkan baik oleh serangkaian biokimia perubahan dalam sel atau oleh modifikasi potensial membran sel dengan gerakan ion dalam atau di luar sel. Reseptor yang memulai biokimia perubahan dapat melakukannya baik secara langsung melalui kegiatan enzimatik intrinsik dalam reseptor atau dengan mengaktifkan molekul pembawa intraseluler.Sinyal transducing reseptor adalah empat kelas umum: Reseptor yang menembus membran plasma dan memiliki aktivitas enzim intrinsik atau enzim yang berhubungan (tertaut enzim reseptor) Reseptor yang ditambah, di dalam sel, untuk protein G (7-TM reseptor) Reseptor yang ditemukan intra seluler dan ligan mengikat langsung mengubah transkripsi gen (transkripsi) Ion ligan-gated saluranThe intracellular component of signal transduction is highly receptor specific, thereby maintaining the specificity of the incoming signal inside the cell. Signal transduction pathways amplify the incoming signal by a signaling cascade using a network of enzymes that act on one another in specific ways to ultimately generate a precise and appropriate physiological response by the cell. Signal transduction involves altering the behavior of proteins in the cascade, in effect turning them on or off like a switch. Adding or removing phosphates is a fundamental mechanism for altering the shape, and therefore the behavior, of a protein. Several small molecules within the cell act as intracellular messengers (also known as second messengers). These include cAMP, cGMP, nitric oxide, lipids and Ca2+ ions. Activated receptors stimulate second messenger production, which in turn activate other enzymes and so the cascade continues.