Developmental Evolution of Fertilization Biology In Ancient Angiosperm Lineages

1有计划研究的更广泛影响的奖励摘要和陈述在经历了很长一段时间的经验和知识停滞之后，许多关于被子植物多样化初期阶段的百年范例正在被重写。现在的证据表明，被子植物进化的最早阶段可能具有非常高的发育实验和结构不稳定性的特征。与研究古代被子植物的花形态、营养解剖学和生态生理学进化的共同努力相比，很少有人关注重建开花植物胚胎学特征的早期多样性。这项计划研究的明确目标是从进化发展的角度研究雌配子体发育、双受精和胚乳形成的基本和高度相关的过程，特别是选择一组物种来代表基本开花植物分支的多样性。将解决以下四个相互关联的问题：1)最早开花的植物是否具有双受精过程，2)原始被子植物雌配子体的发育模式和成熟结构是什么？3)在基本被子植物谱系中是否存在以前没有记载的雌性配子体的发育模式和成熟结构？4)早期被子植物胚乳的倍性和遗传结构(如父本基因组比)是如何进化的？除了建立可以解释雌配子体结构、胚乳遗传结构和倍性多样性的一般发育原理外，这项计划中的研究还将对了解开花植物进化多样化早期阶段性状进化的节奏和模式做出更一般的贡献，对科学中的人力资源开发具有重要意义。弗里德曼实验室的成员(本科生、研究生、博士后、技术人员)有机会解决进化生物学中一些最基本和最长期存在的问题，并培养独立的智力技能。实验室的所有成员都肩负着重大的科学责任。一位名叫埃里克·马德里的博士生是科学界一个代表性较低的群体(西班牙裔)的成员。他将直接得到拟议的研究拨款的支持。埃里克致力于提高少数群体参与科学的程度的外展努力，并已经在为科学界其他代表性不足的成员树立榜样方面产生了重大影响。目前，弗里德曼实验室的大多数成员都是女性，他们渴望在生命科学领域从事教育工作者和/或执业科学家的职业。科尔斯滕·赖尔森是一名技术人员，他将得到拟议的研究拨款的支持，他计划进入公立学校的科学教育职业生涯。明年秋天，她将开始努力争取获得科罗拉多州的教师资格证书。她直接参与了弗里德曼实验室的研究，应该会直接让她未来的生物学学生受益。另一位将得到计划中的研究拨款支持的技术人员阿曼达·雷德福热衷于寻找导致研究生学习的研究机会。最后，通过REU计划，本科生将被支持在国际和平研究所的实验室获得第一手研究经验，威廉·弗里德曼。从本质上讲，虽然与这项提议相关的绝大多数资金将用于支持解决基本和长期存在的科学问题，但这些资金将在支持下一代生命科学家和教育工作者的发展方面发挥关键作用。最后，预计从计划研究中得出的基本发现将像过去一样，被纳入大学水平的教科书中。因此，这项研究应该会对全美的本科生和研究生课程发展产生影响。

1Award Abstract and Statement of Broader Impacts of Planned ResearchAfter a long period of empirical and intellectual stagnation, many of the century-old paradigms about theinitial phases of the diversification of angiosperms are in the midst of being rewritten. It is now evidentthat the earliest phases of angiosperm evolution may have been characterized by a very high degree ofdevelopmental experimentation and structural lability. In contrast to concerted efforts to study theevolution of floral morphology, vegetative anatomy and ecophysiology among ancient angiospermlineages, little attention has been paid to reconstructing the early diversification of embryological featuresamong flowering plants. It is the explicit goal of the planned research to study the basic and highlyinterrelated processes of female gametophyte development, double fertilization, and endosperm formationfrom an evolutionary developmental perspective in a set of species specifically chosen to represent thebreadth of diversity among basal clades of flowering plants.The following four interrelated questions will be addressed: 1) Did the earliest flowering plants possess aprocess of double fertilization, and have some ancient angiosperm lineages lost this process? 2) What wasthe developmental pattern and mature structure of the ancestral angiosperm female gametophyte? 3) Arethere additional and previously undocumented developmental patterns and mature structures of femalegametophytes among basal angiosperm lineages? 4) How has ploidy and genetic constitution (e.g. thematernal to paternal genomic ratio) of early angiosperm endosperm evolved? Beyond establishinggeneral developmental principles that can explain the diversification of female gametophyte structure andendosperm genetic structure and ploidy, the planned research will make a significant contribution tounderstanding more general aspects of the tempo and mode of character evolution during the earliestphases of the evolutionary diversification of flowering plants.The proposed research will contribute significantly to the development of human resources in thesciences. Members of the Friedman lab (undergraduates, graduate students, postdoctorals, technicians)have the opportunity to grapple with some of the most basic and longstanding questions in evolutionarybiology, and to develop independent intellectual skills. All members of the lab are charged withsignificant scientific responsibility. One Ph.D. student, Eric Madrid, is a member of an underrepresentedgroup in the sciences (Hispanic). He will be directly supported by the proposed research grant. Eric iscommitted to outreach efforts to improve the level of participation of minorities in the sciences andalready has had a major impact in serving as a role model for other members of underrepresented groupsin the sciences.Currently, most of the members of the Friedman lab are women and aspire to careers in the life sciencesas educators and/or practicing scientists. One technician, Kirsten Ryerson, who will be supported by theproposed research grant, plans to enter a career in public school science education. She will beginworking towards a teaching certificate for the state of Colorado next fall. Her direct engagement inresearch in the Friedman lab should directly benefit her future biology students. Another technician whowill be supported by the planned research grant, Amanda Redford, is keen to pursue researchopportunities that will lead to graduate study. Finally, through the REU program, undergraduates will besupported to gain first hand research experience in the laboratory of the PI, William Friedman. Inessence, while the vast majority of funds associated with this proposal will go to support the solution ofbasic and longstanding scientific questions, these funds will play a critical role in supporting thedevelopment of members of the next generation of life scientists and educators.Finally, it is anticipated, that the basic findings derived from the planned research will, as has been thecase in the past, be covered in college level textbooks. Thus, the research should have an impact onundergraduate and graduate curriculum development throughout the U.S.