Esinye indawo esithakazelisayo sezindawo zokucwaninga isikhathi eside kuma-telomeres, okuyizinto "amathiphu" ekugcineni kwe-chromosomes yethu, eyakhiwe ngokulandelana kwe-DNA engenayo ikhodi. I-Telomeres idlala indima ebalulekile empilweni yabantu kanye nabososayensi abathola ukuthi bawina umklomelo weNobel ePhysiology noma Medicine ngo-2009.
Lapho amangqamuzana azokuhlukanisa, i-DNA kufanele ilandiswe.
I-enzymes eyenza inqubo yokuphindaphinda iqala ngokugodla kuze kube sekupheleni kwe-chromosome. Ingxenye ye-chromosome lapho umshini wokuphindaphinda ungahlanganiswa khona, ngakho-ke ngokuhlukaniswa kweseli ngayinye, i-chromosome ingasho ukuthi ibe mfushane. Ukuncishiswa kwe-Telomere kuyinkomba yokuguga kwamaselula. I-Telomeres yizingxenye ze-DNA emaphethelweni we-chromosomes enikeza indawo imishini yokuphindaphinda yokunamathisela, ukuze i-DNA strand ingalandelwa ngokuphelele. Ukuze kube nokunye ukuphindaphindiwe okwenzekayo, kufanele kube khona okwanele kwe-telomere eseleyo ukuhlinzeka indawo ye-enzyme yokuphindaphinda ukuze ifake, ukugcina imigqa yesibalo sezinhlayiya zezinhlayiyana eziphelele futhi iyatholakala ukuze ikopishwe. Uma i-telomere iba mfushane kakhulu, ukuphindaphinda kwe-DNA kuyonakele, futhi iseli ngeke lihlukanise. Amaseli anezinqubo ezikhona zokugcina ama-telomere. I-enzyme telomerase yakha kabusha ama-telomere, ukubuyisela ukufinyezwa okwenzeka ngokuhlukana kweseli ngalinye.
Ukuguga kwamaselula kuholela ku-Senescence yeselula
Ukuguga kwamangqamuzana, okufaka ukulimaza kwe-telomere kanye nokulimala kwe-DNA, ekugcineni kubangele ukushona kwe-senescence, isimo sokuboshwa kwamaselula. Iseli isaphila, kodwa ayinempilo futhi ayikwazi ukuhlukanisa. Njengoba amangqamuzana amaningi nangamaqanda abe yisisenecent, ngokuyisisekelo izicubu ziguga, umsebenzi wawo uhlehliswa.
Amangqamuzana asesimeni akakwazi ukwenza izinqubo ezivamile zamangqamuzana, abulale ikhono lamathisiphi lokulungisa umonakalo, nokufaka izinto eziphathekayo ezithinta kabi ukusebenza kwamangqamuzana angomakhelwane futhi zikhuthaza ukuthuthukiswa komdlavuza.
Ama-Telomeres ambalwa ahlanganiswe nezifo
Ubude be-Telomere nomsebenzi we-telomerase kungalinganiswa kumaseli omhlophe egazi omuntu, futhi lokhu kuye kwabanikeza abacwaningi amandla okuphenya izici nezifo ezithinta izibopho kulezi zimpawu zokuguga kwamaselula.
Ezifundweni zabantu, ubude obuncane bokuthi ubude be-telomere noma umsebenzi ophansi we-telomerase buhlotshaniswa nezifo ezingapheli, ezivimbelayo, kuhlanganise nesifo somfutho wegazi, isifo senhliziyo, ukushukela kwe-insulin, uhlobo lwesifo sikashukela, ukucindezeleka, i-osteoporosis, nokukhuluphala.
Ukudla nokuphila kwezinto zokuphila kubuthinta ubude be-Telomere
Ubude be-Telomere nomsebenzi we-telomerase kuthintwa yizo zombili izithonya zofuzo nezemvelo, kuhlanganise nokudla nokukhetha kokuphila. Izinga eliphezulu kakhulu lokusetshenziswa kwemifino nezithelo, ukufakelwa kwefayibha, ukutholakala kwamavithamini nokumbiwa kwamaminerali, nokuzivocavoca yizinto ezihlobene nama-telomeres asele kanye nomsebenzi omkhulu we-telomerase. Ukulondoloza i-telomere kubonakala sengathi kuyindlela yezinqubo eziningi zokuziphatha ezikhuthazayo ezikhuthaza impilo ende.
Imithombo:
Burton DG, Krizhanovsky V. Imiphumela engokwemvelo kanye neyentengiselwano ye-senescence yeselula. Cell Mol Life Sci 2014, 71: 4373-4386.
Cassidy A, De Vivo I, Liu Y, et al. Izinhlangano eziphakathi kokudla, izici zokuphila, nobude be-telomere kubesifazane. Am J Clin Nutr 2010, 91: 1273-1280.
Deng W, Cheung ST, Tsao SW, et al. Umsebenzi we-Telomerase nokuhlangana kwawo nokucindezeleka kwengqondo, ukuphazamiseka kwengqondo, izici zokuphila kanye nokungenelela: Ukubuyekezwa okuhlelekile. I-Psychoneuroendocrinology 2016, 64: 150-163.
Umphumela wezinguquko ezinzulu zokuphila emisebenzini ye-telomerase nobude be-telomere emadodeni ane-biopsy-etholakala engozini engozini yomdlavuza wesifo sofuba: ukulandelwa kweminyaka engu-5 kwesifundo somshayeli esichazayo.
Marcon F, Siniscalchi E, Crebelli R, et al. Ukunciphisa i-telomere yokuhlobene nokudla nokuqina kwe-chromosome. Mutagenesis 2012, 27: 49-57.