植物分类学报
植物分類學報
식물분류학보
ACTA PHYTOTAXONOMICA SINICA
2008年
1期
23-31
,共9页
CYCLOIDEA基因%表达模式%花对称性%苦苣苔科%大叶石上莲
CYCLOIDEA基因%錶達模式%花對稱性%苦苣苔科%大葉石上蓮
CYCLOIDEA기인%표체모식%화대칭성%고거태과%대협석상련
CYCLOIDEA%expression pattern%floral symmetry%Gesneriaceae%Oreocharis benthamii.
CYC 类基因的分子系统学研究已经在苦苣苔科Gesneriaceae中展开, 但是还缺乏对这些基因表达和功能的研究.因此, 我们选择苦苣苔科大叶石上莲Oreocharis benthamii作为实验材料, 分离出了CYC类基因的两个拷贝, 经过分子系统学分析这两个基因分别属于苦苣苔科GCYC1和GCYC2两个分支, 故命名为ObCYC1和ObCYC2.分区的RT-PCR实验结果显示这两个基因拥有不同的时间空间表达模式.ObCYC1与模式植物金鱼草Antirrhinum majus中的CYC基因类似, 集中在花冠背部区域表达, 这与它们拥有保守的功能区TCP和R相一致.但是, ObCYC1与CYC表达模式仍有区别, 即, 和CYC相比ObCYC1在花冠背部区域的表达提前减弱.这可能和大叶石上莲花冠微弱的两侧对称性相关.另外, 由于大叶石上莲的背部花瓣较两侧和腹部花瓣小, 因此, 在功能上ObCYC1可能起抑制背部花瓣生长作用而CYC基因则促进背部花瓣生长.与ObCYC1不同, ObCYC2的保守功能区有更多的氨基酸位点变化, 而且在RT-PCR实验中也没有检测到它的表达.因此, 需要开展更深入的实验研究分析ObCYC2的基本功能, 这将有助于了解GCYC2类基因在苦苣苔科及其近缘科中的功能和进化途径.
CYC 類基因的分子繫統學研究已經在苦苣苔科Gesneriaceae中展開, 但是還缺乏對這些基因錶達和功能的研究.因此, 我們選擇苦苣苔科大葉石上蓮Oreocharis benthamii作為實驗材料, 分離齣瞭CYC類基因的兩箇拷貝, 經過分子繫統學分析這兩箇基因分彆屬于苦苣苔科GCYC1和GCYC2兩箇分支, 故命名為ObCYC1和ObCYC2.分區的RT-PCR實驗結果顯示這兩箇基因擁有不同的時間空間錶達模式.ObCYC1與模式植物金魚草Antirrhinum majus中的CYC基因類似, 集中在花冠揹部區域錶達, 這與它們擁有保守的功能區TCP和R相一緻.但是, ObCYC1與CYC錶達模式仍有區彆, 即, 和CYC相比ObCYC1在花冠揹部區域的錶達提前減弱.這可能和大葉石上蓮花冠微弱的兩側對稱性相關.另外, 由于大葉石上蓮的揹部花瓣較兩側和腹部花瓣小, 因此, 在功能上ObCYC1可能起抑製揹部花瓣生長作用而CYC基因則促進揹部花瓣生長.與ObCYC1不同, ObCYC2的保守功能區有更多的氨基痠位點變化, 而且在RT-PCR實驗中也沒有檢測到它的錶達.因此, 需要開展更深入的實驗研究分析ObCYC2的基本功能, 這將有助于瞭解GCYC2類基因在苦苣苔科及其近緣科中的功能和進化途徑.
CYC 류기인적분자계통학연구이경재고거태과Gesneriaceae중전개, 단시환결핍대저사기인표체화공능적연구.인차, 아문선택고거태과대협석상련Oreocharis benthamii작위실험재료, 분리출료CYC류기인적량개고패, 경과분자계통학분석저량개기인분별속우고거태과GCYC1화GCYC2량개분지, 고명명위ObCYC1화ObCYC2.분구적RT-PCR실험결과현시저량개기인옹유불동적시간공간표체모식.ObCYC1여모식식물금어초Antirrhinum majus중적CYC기인유사, 집중재화관배부구역표체, 저여타문옹유보수적공능구TCP화R상일치.단시, ObCYC1여CYC표체모식잉유구별, 즉, 화CYC상비ObCYC1재화관배부구역적표체제전감약.저가능화대협석상연화관미약적량측대칭성상관.령외, 유우대협석상련적배부화판교량측화복부화판소, 인차, 재공능상ObCYC1가능기억제배부화판생장작용이CYC기인칙촉진배부화판생장.여ObCYC1불동, ObCYC2적보수공능구유경다적안기산위점변화, 이차재RT-PCR실험중야몰유검측도타적표체.인차, 수요개전경심입적실험연구분석ObCYC2적기본공능, 저장유조우료해GCYC2류기인재고거태과급기근연과중적공능화진화도경.
We isolated and characterized two CYC-like genes from Oreocharis benthamii Clark (Gesneriaceae) in order to investigate their expression patterns. Phylogenetic analysis demonstrates that the two CYC-like genes, ObCYC1 and ObCYC2, belong to GCYC1 and GCYC2 clades in Gesneriaceae, respectively. Gene-specific RT-PCR results show that they have different spatio-temporal expression patterns. ObCYC1 is mainly expressed in the adaxial region of developing flowers as CYC is in Antirrhinum majus. The expression pattern of ObCYC1 demon-strates its basic function of controlling the adaxial floral organ development that is similar to that of CYC in Antirrhinum, which is in correlation with their conserved function domains, i.e. TCP and R domains. However, ObCYC1 is likely to repress the growth of both the adaxial petals and adaxial staminode. In addition, the weak-ened expression of ObCYC1 near flowering is correlated with the flower morphology of Oreocharis which is characteristic of weak zygomorphy. ObCYC2 exhibits a remarkable differentiation in protein sequence of TCP and R domain in comparison with those of ObCYC1 and CYC. Correlatively, ObCYC2 is inactive in floral tissue. This unique feature of ObCYC2 needs to be investigated by further comparative study both in expression and function in order to understand its basic function and evolutionary pathway in Gesneriaceae and related families.
