He lōʻihi loa nā mea kanu, e kulou ana i hiki ke komo i ka lā i kēlā me kēia lau. ʻOiai ka nānā ʻana i kēia hanana no nā kenekulia, ʻaʻole maopopo ka poʻe ʻepekema. I kēia manawa ua ʻike nā kānaka ʻepekema ma Salk Institute ʻelua mau mea kanu - ʻo ka protein PIF7 a me ka ulu ʻana o ka hormone auxin - nā mea hoʻoulu e wikiwiki i ka ulu ʻana i ka wā e ulu ana nā mea kanu i ka malu a hōʻike i nā mahana kiʻekiʻe i ka manawa like. punaewele kūhelu o ke kula.
ʻO nā mea i ʻike ʻia, i paʻi ʻia ma ka puke pai Nature Communications ma ʻAukake 29, 2022, e kōkua i nā ʻepekema e wānana i ka pane ʻana o nā mea kanu i ka hoʻololi ʻana i ke aniau a hoʻonui i nā hua ʻoiai ka hoʻomehana honua e hōʻino ana i nā mea kanu.
"I kēia manawa, ke ulu nei mākou i nā mea kanu ma kahi kikoʻī, akā hōʻike kā mākou mau hopena e pono mākou e hoʻohaʻahaʻa i ka nui o ka ulu ʻana i ka ulu ʻana o ka mea kanu i ka hoʻololi ʻana o ke aniau," wahi a ka mea kākau kiʻekiʻe ʻo Professor Joanne Chory, ka luna o ka Salk Institute's Plant Molecular a me Cell Biology Laboratory a me Howard, mea noiʻi ma ka Hughes Medical Institute. "ʻO ka hoʻomaopopo ʻana i ke kumu molekala o ka pane ʻana o nā mea kanu i ka mālamalama a me ka mahana e hiki ai iā mākou ke hoʻoponopono maikaʻi i ka nui o ke kanu ʻana e hoʻohua i nā hua maikaʻi loa."
I ka wā o ka hoʻoulu ʻana, hoʻolōʻihi koke nā mea kanu i ko lākou mau ʻōpala e wāwahi i ka lepo a hopu koke i ka lā. ʻO ka maʻamau, hoʻolohi ke kumu i kona ulu ʻana ma hope o ka ʻike ʻana i ka lā. Akā hiki ke hoʻolōʻihi hou ke kumu inā hoʻokūkū ka mea kanu me nā mea kanu a puni no ka lā a i ʻole e hoʻonui i ka mamao ma waena o ka ʻāina wela a me nā lau o ka mea kanu no ka piʻi ʻana o ka mahana. ʻOiai ʻo nā kūlana kaiapuni ʻelua - ka malu a me nā mahana kiʻekiʻe - e hoʻoulu i ka ulu ʻana o ke kumu, hoʻemi pū lākou i nā hua.
I loko o kēia haʻawina, ua hoʻohālikelike nā ʻepekema i nā mea kanu e ulu ana i ka malu a me nā mahana wela i ka manawa like - nā kūlana e hoʻohālike i ka density kanu kiʻekiʻe a me ka hoʻololi ʻana i ke aniau. Ua hoʻohana ka poʻe ʻepekema i ka mea kanu kumu hoʻohālike ʻo Arabidopsis thaliana, a me ka ʻōmato a me kahi pili pili o ka paka, no ka mea makemake lākou e ʻike inā pili like nā ʻano mea kanu ʻekolu i kēia mau kūlana kaiapuni.
Ma nā ʻano ʻekolu a pau, ua ʻike ka hui o nā mea noiʻi ua ulu nui nā mea kanu i ka manawa like i hoʻāʻo e pale i ka malu i hana ʻia e nā mea kanu e pili ana a ua ʻike ʻia i nā mahana kiʻekiʻe. Ma ka molecular level, ua ʻike nā mea noiʻi ʻo ka PIF7 transcription factor, kahi protein e kōkua ai i ka hoʻohuli ʻana i nā genes a i ʻole, ua kōkua i ka hoʻonui ʻana i ka ulu. Ua ʻike pū lākou i ka piʻi ʻana o ke kiʻekiʻe o ka auxin, kahi hormone ulu, i ka wā i loaʻa ai nā mea kanu i nā mea kanu kokoke, e hāpai ana i ka ulu ʻana i ka pane ʻana i nā mahana kiʻekiʻe. Ua ʻae kēia ala synergistic PIF7-auxin i nā mea kanu e pane i ko lākou kaiapuni a hoʻololi i ka ʻimi ʻana i nā kūlana ulu maikaʻi loa.
ʻO kahi kumu transcription pili, PIF4, hoʻoulu pū i ka elongation stem ma nā wela kiʻekiʻe. Eia nō naʻe, me ka hui pū ʻana o ka malu a me nā mahana kiʻekiʻe, ʻaʻole i hana nui kēia mea.
"Pīhoihoi mākou i ka ʻike ʻana ʻaʻole he kuleana koʻikoʻi ka PIF4 no ka mea ua hōʻike nā haʻawina mua i ke koʻikoʻi o kēia mea i nā kūlana ulu e pili ana," wahi a ka mea kākau noiʻi mua ʻo Yogev Burko, he hoa noiʻi ma ka Salk Institute a me kahi kumu aʻoaʻo ma ka ʻO ka hui no ka noiʻi mahiʻai ma ka Israel Volcanoes Institute. "ʻO ka ʻoiaʻiʻo ʻo PIF7 ka mea hoʻokele ulu nui no kēia mea kanu he mea kupanaha maoli. Me kēia ʻike hou, manaʻolana mākou e hoʻoponopono maikaʻi i ka pane o ka ulu ʻana o nā mea kanu like ʻole e kōkua iā lākou e hoʻololi i ka hoʻololi ʻana i ke aniau.
Manaʻo nā mea noiʻi aia kekahi kumu ʻē aʻe e ʻike ʻia e hoʻonui i ka hopena o PIF7 a me auxin. Manaʻo lākou e ʻimi i kēia mea ʻike ʻole i nā haʻawina e hiki mai ana. E aʻo pū ka lab o Berko pehea e hiki ai ke hoʻomaikaʻi ʻia kēia ala i nā mea kanu.
"Ke piʻi nei ka mahana o ka honua, no laila pono mākou i nā meaʻai e hiki ke ulu i kēia mau kūlana hou," wahi a Chori, ke alakaʻi alakaʻi o ka Salk Plant Use Initiative a me Howard H. a me Maryam R. Newman Chair of Plant Biology. "Ua ʻike mākou i nā kumu koʻikoʻi e hoʻoponopono i ka ulu ʻana o nā mea kanu i nā wela kiʻekiʻe, e kōkua iā mākou e ulu i nā mea kanu ʻoi aku ka maikaʻi e hānai i nā hanauna e hiki mai ana."