Nhoroondo yekusikwa kwedzidziso yaHayflick
Leonard Hayflick (akaberekwa May 20, 1928 muPhiladelphia), purofesa weanatomy paUniversity of California kuSan Francisco, akatanga dzidziso yake paaishanda paWistar Institute muPhiladelphia, Pennsylvania, muna 1965. Frank MacFarlane Burnet akatumidza dzidziso iyi zita raHayflick bhuku rake rine musoro unoti Internal Mutagenesis, rakabudiswa muna 1974. Pfungwa yeHayflick limit yakabatsira vesainzi kuti vadzidze nezvezvinokonzeresa kuchembera kwesero mumuviri wemunhu, kukura kwesero kubva padanho reembryo kusvika parufu, kusanganisira mhedzisiro yekupfupisa kureba kwemagumo emakromosomes anonzi. telomeres.
Muna 1961, Hayflick akatanga kushanda paWistar Institute, kwaakaona kuburikidza nekuona kuti masero emunhu haaparadzani zvachose. Hayflick naPaul Moorehead vakatsanangura chiitiko ichi mune monograph yakanzi Serial Cultivation yeHuman Diploid Cell Strains. Basa raHayflick paWistar Institute rakaitirwa kupa mhinduro inovaka muviri kune vesainzi vakaita ongororo pachikoro ichi, asi panguva imwecheteyo Hayflick aiita tsvakiridzo yake pamusoro pemhedzisiro yehutachiona mumasero. Muna 1965, Hayflick akatsanangura nezve pfungwa yeHayflick muganho mune monograph yakanzi "Limited Lifespan yeHuman Diploid Cell Strains muArtificial Environment".
Hayflick akasvika pamhedziso yokuti sero rinokwanisa kupedzisa mitosis, kureva, nzira yekubereka kuburikidza nekupatsanura, makumi mana kusvika makumi matanhatu chete, mushure mezvo rufu runoitika. Mhedziso iyi yaishanda kumasero akasiyana-siyana, angava evakuru kana masero. Hayflick akaisa mberi fungidziro zvichienderana nekuti iyo diki yekudzokorora kugona kwesero inosanganiswa nekuchembera kwayo uye, zvinoenderana, nekuchembera kwemuviri wemunhu.
Muna 1974, Hayflick akabatanidza National Institute on Aging muBethesda, Maryland.
Sangano iri ibazi reUS National Institutes of Health. Muna 1982, Hayflick akavawo mutevedzeri wasachigaro weAmerican Society for Gerontology, yakavambwa muna 1945 muNew York. Mushure mezvo, Hayflick akashanda kusimudzira dzidziso yake uye kuramba dzidziso yaCarrel yekusafa kweserura.
Kuramba dzidziso yaCarrel
Alexis Carrel, chiremba wokuvhiya wekuFrance aishanda nenyama yehuku mukutanga kwezana ramakore rechimakumi maviri, aidavira kuti masero anogona kuberekana nekusingaperi nekukamukana. Carrel akataura kuti akakwanisa kuzadzisa kupatsanurwa kwemasero emoyo wehuku mune imwe nhanho yekudya - iyi nzira yakaenderera kwemakore anopfuura makumi maviri. Kuedza kwake nenyama yemwoyo yehuku kwakasimbisa dzidziso yokuparadzana kwemasero kusingagumi. Masayendisiti akaedza kakawanda kudzokorora basa raCarrel, asi kuedza kwavo hakuna kusimbisa "kuwanikwa" kwaCarrel.
Kutsoropodza dzidziso yaHayflick
Muma1990, mamwe masayendisiti, akadai saHarry Rubin paYunivhesiti yeCalifornia kuBerkeley, akataura kuti muganho weHayflick unoshanda chete kumaseru akakuvadzwa. Rubin akataura kuti kukuvadzwa kwesero kunogona kukonzerwa nemasero ari munzvimbo yakasiyana nekwaanogara ari mumuviri, kana nevesainzi vanofumura maseru ari murabhoritari.
Kuwedzera tsvakurudzo pamusoro pechiitiko chekukwegura
Zvisinei nekushoropodzwa, mamwe masayendisiti akashandisa dzidziso yaHayflick sehwaro hwekutsvagisazve chiitiko chekuchembera kwemasero, kunyanya matelomeres, anove zvikamu zvekupedzisira zvekromosomes. Telomeres inodzivirira machromosomes uye inoderedza kuchinja kweDNA. Muna 1973, musayendisiti wekuRussia A. Olovnikov akashandisa dzidziso yaHayflick yekufa kwesero muzvidzidzo zvake zvemagumo emakromosomes asingazvibereki panguva ye mitosis. Maererano naOlovnikov, nzira yekuparadzanisa masero inopera nokukurumidza apo sero haichagoni kubereka magumo emakromosomes ayo.
Kwapera gore, muna 1974, Burnet akadaidza dzidziso yeHayflick kuti Hayflick limit, achishandisa zita iri mubepa rake, Internal Mutagenesis. Pamwoyo webasa raBurnet yaive fungidziro yekuti kuchembera chinhu chemukati chinowanikwa mumaseru emhando dzakasiyana dzehupenyu, uye kuti basa ravo rakakosha rinoenderana nedzidziso inozivikanwa seHayflick muganhu, inotangisa nguva yekufa kwechisikwa.
Elizabeth Blackburn weYunivhesiti yeSan Francisco nemumwe wake Jack Szostak weHarvard Medical School muBoston, Massachusetts, vakatendeukira kudzidziso yeHayflick muganho muzvidzidzo zvavo zvemagadzirirwo etelomere muna 1982 pavakabudirira mukugadzira uye kupatsanura matelomere.
Muna 1989, Greider naBlackburn vakatora danho rinotevera mukudzidza chiitiko chekuchembera kwesero nekuwana enzyme inonzi telomerase (enzyme kubva muboka rekutamisa iro rinodzora saizi, nhamba uye nucleotide kuumbwa kwechromosome telomeres). Greider naBlackburn vakawana kuti kuvapo kwetelomerase kunobatsira masero emuviri kudzivirira kufa kwakarongwa.
Muna 2009, Blackburn, D. Szostak naK Greider vakagamuchira Mubairo weNobel muPhysiology kana Mushonga nemashoko okuti “nekuda kwekuwana kwavo nzira dzekudzivirira machromosome nematelomeres uye enzyme telomerase.” Tsvagiridzo yavo yaive yakavakirwa pamuganho weHayflick.