This way includes

This way includes consecutive splitting of biosynthetic precursors: a hormone (pre-about-ptg) ® proparathyroid ® a parathyroid hormone. fiber synthesis occurs on polyribosomes in a cell matrix. Initial amino acid (amino acids) - the methionine, coded by specific Codonum , separates from growing polypeptide chains when it reaches buy purchase cipro at length approximately 20-30 amino acids (the approximate length of a polypeptide covering extent large ). This process is considered the general for synthesis of all fibers produced . Hydrophobic specific for sequence pre-about-ptg, coded by sequence of the bases , immediately adjoining (3-extremity) to initial Codonum (alarm Codonums), acts then in a role of "driver" or a signal which any, till now not found out, provides with image contact of a complex a polyribosome - synthesised a chain with a membrane endoplasmatic . Contacting to this membrane or at the expense of purely hydrophobic interactions, or, that is more probable, at the expense of specific receptors of the membrane, growing polypeptide the chain passes through a membrane in space.
At once after that or, possibly, even in the course of passage pre-about-ptg in the tank the alarm sequence is split off, apparently, under the influence of the specific peptidase, localised in endoplasmatic , that leads to formation about-ptg. This intermediate precursor (about-ptg) moves then on the channels formed by membranes endoplasmatic , to a lamellar complex where from it under action of the enzymes possessing activity, similar to activity of Trypsinum and a carboxypeptidase In, it is split off Mna-trailer . The definitive hormonal product joins in secretory granules and is liberated in extracellular space in reply to depression of concentration of calcium in an extracellular liquid. Correctness of this model proves to be true many data [7-11]. At the structural analysis of primary products of translation of some , coding various cosecreted fibers, it was revealed, that many if not everything, albuminous hormones and cosecreted fibers are synthesised in the beginning in the form of precursors with hydrophobic N1-12-trailer sites (see 3-4). Apparently, the hormone [12] is the typical representative of the whole class of biosynthetic precursors () albuminous hormones which concern insulin, , Prolactinum, and , and also not hormonal cosecreted fibers, such, as pancreas enzymes, egg white proteins, immunoglobulins, buy purchase rimonabant a seralbumin,(or Mellitinum - bee sting) and some with a membrane bacteriemic fibers. For alarm sequences of precursors that they are located on a NH2-trailer part of fibers is characteristic. These sequences differ on length, including from 15 to 25 amino-acid rests; in their central parts the hydrophobic site consisting of 10 12 amino acids contains. So high degree of water repellency is characteristic for the fibers known for the specific interaction with membranes. The cited data allow to consider, that a movement possibility through a membrane - the basic function of alarm sequence. Thus, thanks to specific character of sequence of the precursor from set of cellular fibers are selected, separate, transported and the fibers intended for secretion arrive on the secretory conveyor of a cell. If in the relation or there are weighty proofs of their transport function function intermediate predshestvennikov-progormonov-remains the unknown person. Autoradiographic researches of migration of again synthesised fibers in a cell have shown, that transformation of a prohormone into end-products occurs in a lamellar complex of a cell. For example, the period in 15 mines between the beginning sip-teza pre-about-ptg and first occurrence practically coincides with the term necessary for hit of autoradiographic granules in a lamellar complex [13]. Transformation of a prohormone into a hormone can be selectively blocked also action on a tissue of inhibitors of production of energy in a cell ( And and ), no less than the substances breaking function of microtubules (vinblastine and a colchicine). These data specify that the translocation of a prohormone from in a lamellar complex is volatile process and that microtubules can take part in prohormone movement. However are absent direct that proof, that the prohormone in itself, or its chemical interactions, plays an essential role in transport of again synthesised fiber from in a lamellar complex or that it in any measure defines hormone packing in blisters or granules. Recently carried out researches according to which synthesis of many cosecreted fibers does not demand formation intermediate, or proformas of precursors ( 3-4 see), generate certain doubts in justice of such representation [4].