CAJ | 학술논문

APⅣ是一份多卵水稻突变体.多卵是由"5-2-1"型、"5-3-0"型和"6-2-0"型等蓼型变异型发育途径发育而来的.多卵都能分别受精,因而使APⅣ出现多胚现象.本结果表明,APⅣ中约有一半胚囊的发育属于蓼型变异型,变异型胚囊发育过程中存在多种异常的核行为,这些核行为受着微管骨架组织变化的影响,显示微管骨架组织在胚囊核行为中起着一定的作用.文中观察到的较为明显的异常情况有:"5-2-1"型四核胚囊存在特殊的核运动,四核胚囊刚形成时,珠孔和合点两端各有2个核,但不久合点端有1个核移向珠孔端,形成珠孔端有3个核、合点端只有1个核的特殊四核胚囊.这种四核胚囊在合点端的1个核移向珠孔端期间,合点端2个姐妹核之间存在特殊的长条状微管束,这种微管可能是促进二核有效分开的重要组成部分."5-3-0"型和"6-2-0"型各个时期胚囊内的核行为和核周围的微管组织骨架与同期正常蓼型的胚囊均存在着差异."5-3-0"型二核胚囊1个核位于珠孔端,另1个核近珠孔端,二核呈纵向排列与胚囊纵轴平行,核之间存在随机排列的微管束,因此可能导致二核无法像正常二核胚囊的核一样移向两端."6-2-0"型功能大孢子、二核胚囊和四核胚囊等时期胚囊核均位于珠孔端或近珠孔端,而在核周则存在复杂的网络状微管."6-2-0"型八核胚囊早期除2个近胚囊中央的核存在朝向合点极的长微管(可能有助于推动核向胚囊中央移动)外,其他核周围的微管组织都呈复杂的网络状.
APⅣ시일빈다란수도돌변체.다란시유"5-2-1"형、"5-3-0"형화"6-2-0"형등료형변이형발육도경발육이래적.다란도능분별수정,인이사APⅣ출현다배현상.본결과표명,APⅣ중약유일반배낭적발육속우료형변이형,변이형배낭발육과정중존재다충이상적핵행위,저사핵행위수착미관골가조직변화적영향,현시미관골가조직재배낭핵행위중기착일정적작용.문중관찰도적교위명현적이상정황유:"5-2-1"형사핵배낭존재특수적핵운동,사핵배낭강형성시,주공화합점량단각유2개핵,단불구합점단유1개핵이향주공단,형성주공단유3개핵、합점단지유1개핵적특수사핵배낭.저충사핵배낭재합점단적1개핵이향주공단기간,합점단2개저매핵지간존재특수적장조상미관속,저충미관가능시촉진이핵유효분개적중요조성부분."5-3-0"형화"6-2-0"형각개시기배낭내적핵행위화핵주위적미관조직골가여동기정상료형적배낭균존재착차이."5-3-0"형이핵배낭1개핵위우주공단,령1개핵근주공단,이핵정종향배렬여배낭종축평행,핵지간존재수궤배렬적미관속,인차가능도치이핵무법상정상이핵배낭적핵일양이향량단."6-2-0"형공능대포자、이핵배낭화사핵배낭등시기배낭핵균위우주공단혹근주공단,이재핵주칙존재복잡적망락상미관."6-2-0"형팔핵배낭조기제2개근배낭중앙적핵존재조향합점겁적장미관(가능유조우추동핵향배낭중앙이동)외,기타핵주위적미관조직도정복잡적망락상.
APⅣ is a rice mutant that develops poly-egg apparatus in its embryo sac. All the eggs that make up the poly-egg apparatus can be fertilized respectively resulting in the development of polyembryony.The routes taken in the development of polyembryony appear to fall mainly into three variant polygonum pattern types, designated as "5-2-1", "5-3-0" and "6-2-0" types. Out of the embryo sacs of APⅣ studied about 50% exhibited variant polygonum type with associated abnormal nuclear behavior and microtubule organizational changes. Some of the major abnormal features shown by the three variant polygonum types were described and they included the following: For the "5-2-1" type - At the beginning of the fournucleate embryo sac development, one pair of nuclei became located to the micropylar end and the other pair to the chalazal end. As embryo sac further developed, long connecting microtubule (MT) bundles that existed between the two nuclei in the chalazal end play a role in the movement and positioning of that nucleus. As a result of the activities of these MT, one of the nuclei in the chalazal end moved to the micropylar end resulting in the micropylar end having three nuclei and the chalazal end only one. For the "5-3-0" type - In the two-nucleate embryo sac of the "5-3-0" type, one nucleus remained at the micropylar end, while the other one became located near the central region. In the four-nucleate embryo sac, the pair of nuclei aligned in parallel to the micropylar-chalazal axis often having one of its nuclei relocated to the micropylar end as a result of associated MT activities. For the "6-2-0" type - All the nuclei in the megaspore, two- and four-nucleate embryo sacs became located to the micropylar end. At the early stages of the eight-nucleate embryo sac development, the two nuclei in the central region of the embryo sac (originally at the micropylar end) became polar nuclei. All the other nuclei remained at the micropylar end were surrounded by reticulate MT. The relationship between abnormal behavior of nuclei and MT organi-zation in the development of rice embryo sac was discussed.