Epigenetics muKutonga kweMajini
Epigenetics ibazi rebiology rinoongorora shanduko mumashandiro emajini asingakonzerwi nekuchinja kweDNA sequence. Nemamwe mashoko, epigenetics inotsanangura kuti majini anogona sei kuvhurwa kana kuvharwa pasina kuchinja kodhi yemajini pachayo. Pfungwa iyi yakakosha nekuti inotibatsira kunzwisisa kuti nei masero mumuviri ane DNA imwe chete achigona kuita mabasa akasiyana, akadai semasero etsinga, masero emhasuru, uye masero eropa. Epigenetics inoita basa guru mukudzora majini, maitiro ekudzora kuti jini rinoratidzwa riini, kupi, uye kuti rakasimba sei.
Nheyo dzeKutonga kweMajini
Kudzora majini inzira inoshandiswa nemasero kugadzirisa kugadzirwa kwemapuroteni zvichienderana nezvinodiwa. Majini "Anoshanda" anonyorerwa kuita RNA obva ashandurwa kuita mapuroteni. Majini "Asingashande", kune rumwe rutivi, haagadzire zvigadzirwa zvinoshanda. Kudzora uku kwakakosha pakukura kwemwana ari mudumbu, kusiyanisa masero, kupindura kushushikana, kugadzirisa nharaunda, uye kuchengetedza mashandiro emuviri. Kukanganiswa kwekutonga majini kunogona kutungamira kuzvirwere zvakasiyana-siyana, kusanganisira kenza, kusagadzikana kwemetabolism, uye kusarongeka kwekukura.
Munyaya iyi, epigenetics inoshanda seimwe nzira yekutonga pamusoro pegenome. Kana genome yakaita sebhuku remaresipi, saka epigenetics ndiyo chiratidzo kana chinyorwa chinosarudza kuti ndeapi mabikirwo ekuverenga uye kangani.
Nzira Dzakakosha dzeEpigenetics
Maitiro makuru e epigenetic anokanganisa kurongeka kwemajini. Matatu anonyanya kudzidzwa ndeeDNA methylation, histone modification, uye regulation ne non-coding RNA. Ose matatu anoshanda nenzira yakarongeka kudzora kuwanikwa kweDNA uye mazinga ekutaura kwemajini.
1. DNA methylation
Kusanganiswa kweDNA kunoitika kana boka remethyl (—CH₃) rawedzerwa kune cytosine base, kazhinji munzvimbo dzeDNA dzakapfuma muCpG (cytosine-phosphate-guanine) base pairs. Kuwedzerwa kweboka iri remethyl kunowanzobatanidzwa nekudziviswa kwekugadzirwa kwemajini. Nzvimbo dzakakosha dzemethylation dzinowanzo kuve dzinosimudzira majini, nzvimbo dzeDNA dzinodzora kutanga kwekunyora.
Kana chinhu chinokurudzira chine methyl yakawanda, transcription factors dzinoomerwa nekusunga, uye RNA polymerase haigone kushanda zvakanaka. Nekuda kweizvozvo, gene rinowanzo "nyarara." DNA methylation inoita basa rakakosha mumaitiro akajairwa akadai se X chromosome inactivation muvakadzi uye genomic imprinting, uko magene expression anokanganiswa nemadzitateguru evabereki.
2. Kugadziriswa kweHistone
DNA iri mu cell nucleus haingoparari chete; panzvimbo pezvo, inounganidzwa pamwe chete nemapuroteni ehistone kuti igadzire chromatin. Chimiro ichi chinogona kunge chakasimba kana kuti chakasununguka. Kana chromatin yakabatana (heterochromatin), majini haasvikiki zvakanyanya uye haawanzoonekwi zvakanyanya. Kana chromatin yakasununguka (euchromatin), majini anowanikwa zviri nyore uye anogona kunge achishanda.
MaHistone anogona kugadziriswa zvakasiyana-siyana zvemakemikari, zvakaita seacetylation, methylation, phosphorylation, uye ubiquitination. Histone acetylation, kunyanya pa lysine residues, inowanzobatanidzwa nekushandiswa kwemajini nekuti inoita kuti chromatin ive yakavhurika. Kusiyana neizvi, histone methylation inogona kukonzera kushanda kana kudzvinyirirwa zvichienderana nenzvimbo uye huwandu hwemapoka emethyl akawedzerwa. Kusanganiswa kwekuchinja uku kunoumba "histone code" inobatsira kuona mamiriro ekushandiswa kwemajini.
3. RNA isina makodhi
Haasi maRNA ese anoshandurwa kuita mapuroteni. MaRNA mazhinji asingakodhesi anoita basa guru mukudzora majini, anosanganisira mamicroRNA (miRNAs), maRNA asingakodhesi marefu (lncRNAs), uye maRNA madiki anopindira (siRNAs). Semuenzaniso, maMicroRNA anogona kubatana nemamRNA anotarisirwa uye kukonzera kuora kana kumisa kushandurwa, nokudaro achideredza kugadzirwa kwemapuroteni.
MaRNA asina makodhi anogonawo kutungamira mapuroteni epigenetic kunzvimbo dzakatarwa mugenome, nokudaro achikanganisa DNA methylation kana histone modifications. Nenzira iyi, maRNA asina makodhi anoshanda sevatongi vakagadziriswa zvakanaka vanosarudza mazinga chaiwo ekutaura kwemajini.
Epigenetics muKukura kweSero uye Kusiyanisa
Rimwe remabasa anonyanya kukosha e epigenetics nderekukura kwezvisikwa. Sezvo zygote ichikura kuita mhando dzakasiyana dzemasero, sero rega rega rine DNA imwechete asi rine chirongwa chakasiyana chekutaura kwemajini. Chirongwa ichi chinosimbiswa uye chinochengetwa kuburikidza nezviratidzo zve epigenetic.
Semuenzaniso, masero emuviri ane chromatin yakavhurika, zvichiita kuti majini mazhinji ashande. Sezvaanosiyanisa, zviratidzo zve epigenetic zvinoderedza sarudzo yemajini anobatidzwa, zvichibvumira masero kuti ave akasarudzika, akadai semasero echiropa anobatsira majini ekubvisa detoxification kana masero epancreatic anobatsira majini anogadzira insulin.
Simba rezvakatipoteredza paEpigenetics
Epigenetics inodzivirirawo musiyano uripo pakati pemajini nenzvimbo. Zvinhu zvakaita sekudya kunovaka muviri, kushushikana, kubatwa ne chepfu, kusvuta, kurovedza muviri, uye kunyange maitiro ekurara zvinogona kukanganisa zviratidzo zve epigenetic. Semuenzaniso, kushomeka kwezvimwe zvinovaka muviri zvinoshanda sevanopa methyl (senge folate ne vitamin B12) zvinogona kukanganisa maitiro eDNA methylation.
Kusangana nezvinhu zvinosvibisa kana makemikari kunogonawo kuchinja shanduko dzehistone uye methylation yeDNA, zvichizokanganisa njodzi yezvirwere. Ichi ndicho chimwe chezvikonzero nei mararamiro achigona kukanganisa hutano hwenguva refu, kunyangwe padanho remamorekuru.
Epigenetics uye Zvirwere
Kusawirirana mu epigenetic regulation kunogona kukonzera zvirwere zvakasiyana-siyana. Mukenza, maitiro eDNA methylation anowanzo shanduka zvakanyanya. Mamwe majini anodzvinyirira bundu anogona kunyaradzwa nekuda kwe promoter hypermethylation, zvichitadzisa masero nzira dzekudzora kukura. Kusiyana neizvi, mamwe matunhu e genome anogona kuva hypomethylated, zvichikonzera kusagadzikana kwechromosome.
Pamusoro pegomarara, kukanganiswa kwe epigenetic kwakabatanawo nezvirwere zve neurodegenerative zvakaita se Alzheimer's ne Parkinson's, zvirwere zve metabolic zvakaita se type 2 diabetes, uye zvirwere zve autoimmune. Kunyangwe zvimwe zvirwere zvekukura zvakaita se Prader-Willi ne Angelman syndromes zvakabatana ne epigenetic genomic imprinting.
Epigenetics seChinangwa Chekurapa
Nekuti shanduko dze epigenetic dzinodzoreka, chinangwa chinokwezva chekugadzirwa kwemishonga. Mishonga yakati wandei yegomarara yatove nekushandisa zvinodzivirira ma enzymes anobatanidzwa muDNA methylation kana histone deacetylation, zvakaita seDNMT inhibitors uye HDAC inhibitors. Mishonga iyi inogona kudzorerazve kuratidzwa kwemajini akanyaradzwa, kusanganisira majini anodzvinyirira tumor.
Zvisinei, kurapwa kwe epigenetic kune matambudziko nekuti shanduko dze epigenetic dzinogona kuitika mumajini akawanda panguva imwe chete. Nzira dzakanyatsojeka dzinodiwa kuti pave nemigumisiro yakatarwa uye kuderedza migumisiro yakaipa. Kuvandudzwa kwetekinoroji dzakadai seCRISPR-based epigenome editing kuri kutangawo kuvhura mikana yekuchinja zviratidzo zve epigenetic panzvimbo dzakatarwa dzemajini pasina kucheka DNA.
Epigenetics muNhaka
Mubvunzo mumwe unonakidza ndewekuti shanduko dze epigenetic dzinogona kugara nhaka here. Mune zvimwe zvipenyu, mamwe mavanga e epigenetic anogona kuramba aripo kwezvizvarwa nezvizvarwa. Muvanhu, akawanda mavanga e epigenetic "anodzoserwa" panguva yekuumbwa kwe gamete uye kukura kwekutanga kwe embryonic. Zvisinei, pane zviratidzo zvekuti dzimwe shanduko dzinogona kugara nhaka kuburikidza nenzira dzakaoma, kunyange zvazvo ichi chiri chikamu chekutsvaga chinoshanda.
Mhedziso
Epigenetics chinhu chakakosha mukudzora majini nekuti inosarudza mukana wekuwana DNA uye mazinga ekushandiswa kwemajini pasina kuchinja kurongeka kwemajini. Kuburikidza neDNA methylation, histone modifications, uye non-coding RNA, masero anogona kudzora mashandiro emajini zvichienderana nezvinodiwa pakukura uye mhinduro dzenharaunda. Kunzwisisa epigenetics kunobatsira kutsanangura kusiyana kwemasero, pesvedzero yemararamiro pahutano, uye mavambo ezvirwere zvakasiyana-siyana. Uyezve, epigenetics inopa mikana yakakosha mukurapa, kunyanya nekuda kwehunhu hwayo hunogona kugadziriswa. Nekuenderera mberi nekutsvaga, epigenetics ine mukana wekuva hwaro hwakakosha hwekurapa kwakanyatsojeka uye kwakasarudzika mune ramangwana.
