The function of KNOX proteins in shoot development

KNOX 蛋白在芽发育中的功能

• 批准号: 0445387
• 负责人: Sarah Hake
• 金额: $ 50万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-02-01 至 2008-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0445387&HistoricalAwards=false
• 关键词: function; KNOX; proteins; shoot; development

Hake, Sarah0445387The function of KNOX proteins in shoot developmentPlant growth is determined by small groups of cells called meristems. Meristems produce the leaves, branches and flowers of the plant. Knotted1-like homeobox (knox) genes are expressed in meristems and stems and are required for meristem function and leaf patterning. KNOX proteins are also sufficient for meristematic identity and are able to confer meristem fate on leaves if expressed inappropriately. KNOX proteins are members of the TALE class of transcription factors that are conserved in animals and plants. They function as biochemical partners with BEL1-like (BELL) proteins to bind DNA and thus regulate transcription. There are eight KNOX proteins and 13 BELL proteins in Arabidopsis. The proposed research will determining which KNOX protein interacts with which BELL protein and in what cell compartment and in what tissue. These experiments will be carried out in Arabidopsis. Biochemical experiments will also determine what genes are regulated by KNOX proteins in maize and rice by identifying the DNA which is bound by KNOX proteins and following transcription profiles. The third aim is to determine what are the regulatory sequences that keep knox genes from being expressed in leaves. A number of dominant mutants exist in maize that misexpress knox genes in leaves. Similar mutations are found in barley and snapdragon. These mutations all have rearrangements in intronic sequences, the part of the gene that does not code for protein. Molecular genetic experiments will determine what are the important sequences that keep knox genes from being expressed in leaves. The information gained from these experiments will provide an understanding of plant architecture and lead to improved crop yields. During the summer, a high school chemistry teacher from San Francisco will join the graduate students on the project to participate in the biochemistry experiments. In addition, the PI will bring genetics to the 7th grade of a rural middle school each spring to look at genetic ratios segregating on maize ears and isolate DNA.

Hake，Sarah 0445387 KNOX蛋白在芽发育中的功能植物的生长是由称为分生组织的小细胞群决定的。分生组织产生植物的叶、枝和花。 knotted 1-like homeobox（knox）基因在分生组织和茎中表达，是分生组织功能和叶形成所必需的。KNOX蛋白对于分生组织身份也是足够的，并且如果不适当地表达，则能够赋予叶分生组织命运。KNOX蛋白是动物和植物中保守的TALE类转录因子的成员。它们作为生化伴侣与BEL 1样（BELL）蛋白结合DNA，从而调节转录。拟南芥中有8个KNOX蛋白和13个BELL蛋白。拟议的研究将确定哪种KNOX蛋白与哪种BELL蛋白相互作用，以及在什么细胞区室和什么组织中相互作用。 这些实验将在拟南芥中进行。 生物化学实验也将通过鉴定与KNOX蛋白结合的DNA和转录谱来确定玉米和水稻中哪些基因受KNOX蛋白的调控。第三个目标是确定是什么调控序列阻止knox基因在叶子中表达。玉米中存在着许多显性突变体，它们在叶片中错误表达knox基因。在大麦和金鱼草中也发现了类似的突变。这些突变都在内含子序列中发生重排，内含子序列是基因中不编码蛋白质的部分。分子遗传学实验将确定是什么重要的序列使knox基因在叶子中不被表达。从这些实验中获得的信息将提供对植物结构的理解，并提高作物产量。在夏季，一位来自旧金山弗朗西斯科的高中化学老师将加入该项目的研究生，参加生物化学实验。此外，PI每年春天将把遗传学带到一所农村中学的七年级，研究玉米穗上分离的遗传比率并分离DNA。