The degeneracy of majini code: zvinokosha

The majini Bumbiro kunoratidzirwa sezvo codons, kwegadziriro yeEncoding ruzivo nemamiriro mapuroteni, tinoberekwa zvose zvipenyu panyika. Decryption kutora emakore, asi kuti iye aripo, sainzi zvinonzwisiswa anenge zana. Pakawanda, specificity, unidirectional, uye kunyanya degeneracy pakati majini remitemo vane chaivo kukosha.

History of Zvavakawana

The dambudziko yeEncoding majini information kwagara anokosha zvipenyu. By chizvaro nemamiriro nemagene code, sainzi mberi asi zvishoma nezvishoma. Sezvo kuwanikwa J. Watson uye Crick muna 1953. The kaviri akamonyoroka maumbirwo DNA akapinda danho kugadzirisa bumbiro yakarongeka pacharo, iro chakaita kutotenda noukuru zvakasikwa. The Linear maumbirwo mapuroteni uye DNA zvakafanana mamiriro kunanga kuvapo majini code, kuti tsamba pakati magwaro maviri, asi zvakanyorwa pamwe bumbiro zvakasiyana. Uye kana arufabheti kwemapurotini rave richizivikanwa, DNA mavanga aiva nyaya dzokudzidza zvipenyu, wefizikisi uye masvomhu.

Hapana chikonzero kutsanangura zvose nhanho vari kugadzirisa kuti kutadza kunzwisisa ichi. Direct kuedza, akaratidza uye akasimbisa kuti pakati DNA codons uye amino acids pamusoro puroteni pane akajeka uye inowirirana azvaitwa wakaitwa muna 1964 Charles Janowski uye S. Brenner. A mberi - panguva decoding pakati majini remitemo ezvokunambira kunze kwomuviri waamai (ezvokunambira kunze kwomuviri waamai) kushandisa unyanzvi mapuroteni usage muchitokisi isina hurongwa.

Fully decrypted Bumbiro E. Coli akanga hauitirwi muna 1966, nyanzvi dzezvinhu zvipenyu panguva yokusiyirana pana Cold Spring Harbor (USA). Ndakabva akazarura redundancy (degeneracy) of majini remitemo. Chii ichi zvinoreva kuti akatsanangura zvikuru nyore.

decoding mberi

Kuwana achiongorora zvaive nhaka remitemo Data yazova chimwe chezvinhu zvinokosha wekupedzisira remakore. Nhasi, sainzi anoramba kuongorora zvakadzama zviri zvigadziriswe ezvinhu yeEncoding maitiro uye mamiriro ayo uye overabundance zviratidzo, chii runoratidzwa enzvimbo degeneracy pakati majini remitemo. A yoga Kudzidza indasitiri - kwakabva uye Kushanduka enhaka zvinhu Coding hurongwa. Uchapupu unobatanidza polynucleotides (DNA) uye polypeptides (mapuroteni) zvakasimbisa kukura ezvinhu zvipenyu. Uye kuti, akavapindurawo, hwokushandura zvinhu zvipenyu, bioengineering, zvakawanikwa munyika maberekero uye chirimwa kukura.

Nevanhu uye mitemo

Home dzidziso ezvinhu zvipenyu - mashoko ari kubva DNA kuti mutumwa RNA, uye ipapo naye pamusoro puroteni. In nevakomana kutungamirirwa yedzimudzangara zvinogoneka kubva RNA kuti DNA uye RNA vamwe RNA.

Asi chizvaro kana hwaro DNA nguva dzose inoramba. Uye vose mumwe zvinhu zviri mashoko kuchinjirwa - kupangidza yezvakaita kuchinjwa chizvaro. Kureva, nokuita Kupfuudzwa kuti kwetunhu mamwe chizvaro mamorekuru, izvo zvichaita kubereka ari maumbirwo magene mashoko.

nemagene remitemo

Line Coding mamiriro mapuroteni mamorekuru achishandisa nopindirana codons (vatatu) nucleotides, izvo chete 4 (adein, guanine, cytosine, thymine (uracil)), izvo nomuzvarirwo kunotungamirira kuti paumbwe dzimwe namaketani nucleotides. Chete Nhamba nucleotides uye makemikari complementarity - ndicho chikuru zvimiso kwetunhu kwakadaro. Asi paumbwe imwe puroteni Morekuru unhu chienderane kuti uwandu uye chatingatevedzera monomers haisi (DNA nucleotides - mapuroteni amino acids). Ndiyo dzinongoitika nhaka remitemo - kurekodha wemuTesitamende kutevedzana kwezviitiko nucleotides (codons) ari amino iine acid kutevedzana kwezviitiko puroteni.

Genetic remitemo ine zvivako dzakawanda:

• Triplet.
• Kusiyana.
• Dzidziso.
• Disjointness.
• Redundancy (degeneracy) of majini remitemo.
• Pakawanda.

Heino imwe tsananguro pfupi, pfungwa pamusoro zvipenyu kukosha.

Triplet, akaramba uye Kuwanikwa stoplights

Mumwe nomumwe 61 amino acids unoenderana munhu kupindirana kwemuvanzrira wezvirevo nemabviro T (triplet) nucleotides. vatatu vatatu musatakura ruzivo pamusoro amino asidhi uye vari chemabhazi codons. nucleotide nomumwe ari cheni ndiyo nhengo triplet, uye hakuwaniki pacharwo. Panopera uye kutanga kwezviitiko nucleotides unoenderana chete mapuroteni, muri chemabhazi codons. Vanotanga kana vanorega nhepfenyuro (the kwetunhu ane puroteni Morekuru).

Specificity, uye mumwe-pointedness disjointness

Mumwe codon (triplet) inofananidzira mumwe chete amino acid. Mumwe triplet ndiko kuzvitonga uye asingauyi bindepinde pedyo. Imwe nucleotide anogona kuva triplet mumwe chete ari cheni. Protein usage anogara rimwe divi chete, kuti rinodzorwa chemabhazi codons.

The redundancy of majini remitemo

Mumwe triplet pamusoro nucleotides inofananidzira mumwe amino acid. Vanosvika 64 nucleotides, 61 vavo - encoded amino asidhi (pfungwa codon), uye nhatu - maturo, kureva amino asidhi hakuiti encode (kurega codons). The redundancy (degeneracy) of majini code kuti vokutsiva zvinogona kuitwa neimwe triplet - kukuru (kunotungamirira amino iine acid yokutsiva) uye kuchinja (amino acids handishanduki kirasi). Zviri nyore kuverenga kuti kana munhu triplet anogona kuitwa 9 vokutsiva (1, 2 uye 3 nzvimbo), mumwe nucleotide inogona kutsiviwa 4 - 1 = 3 mumwe musimboti, uwandu zvichibvira nucleotide vokutsiva zvichava 61 kusvika 9 = 549.

The degeneracy of majini remitemo unoratidzwa yokuti 549 zvokusarudza - zviri zvikuru kupfuura zvakafanira kuti zakodirovki mashoko anenge 21 amino acids. In ichi nyaya yokutsiva nzira 549 23 achitungamirira paumbwe kumisa codon, 134 + 230 kuzvitsinhanisa - vari kuchinja vokutsiva, uye 162 - kukuru.

Ushe degeneracy uye kunze

Kana codons maviri maviri akafanana yokutanga nucleotide, ivo nucleotides vasara dzinoturwa pamwe boka (purine kana pyrimidine), Vanotakura chete amino asidhi mashoko. Kazhinji ichi ndicho degeneracy kana redundancy kuti majini remitemo. Two anosiyiwa - Aua uye UGA - kutanga inofananidzira methionine, kunyange zvazvo aifanira isoleucine, uye wechipiri - kumisa codon, asi aizofanira encode tryptophan.

Zvichireva degeneracy uye pakawanda

Izvi ehupfumi maviri majini remitemo vane chemhando chaivo ukoshi. Ose ehupfumi pamusoro apa dziri yo majini mashoko kwose zvipenyu zviri redu.

The degeneracy of majini remitemo aine adaptive kukosha, sezvo kudzokororwa kuburitsa mufananidzo mumwe chete amino asidhi yekubvuma. Uyezve, ichi chinomirira chinokosha zvinoderedza (degeneration) wechitatu nucleotide ari codon. Yakadaro musimboti waanodzikisira ari mutational maronda DNA, izvo kunotoreva zvakakomba yokutyora ari puroteni mamiriro. Ichi rwokudzivirira mashandiro zvipenyu zviri panyika.