An Investigation of Biophysical Variables in Stiff and Hypertropic Mutant Sporangiophores of Phycomyces Blakesleeanus

首席研究员（PI）之前的研究已经推导、发展并建立了定量的生物物理方程，这些方程描述了黑藻菌（Phycomyces blakesleeanus）和其他有壁细胞（即藻类、真菌和植物细胞）的大圆柱形单细胞孢子囊的膨胀生长。当前研究项目的目的是通过使用表现出异常生长行为的突变孢子囊，深入了解控制膨胀生长和生长行为的生物物理变量和相关生物过程之间的关系。研究将集中在刚性和增生性突变孢子囊菌株上，它们分别表现出弱和增强的热带反应和生长反应。将进行生物物理实验，以确定相关的生物物理变量的大小和行为的刚性和增生性突变孢子囊。所得结果将与野生型孢子囊的结果进行比较。先前NSF Grant （MCB-0640542）的研究提出了一种真菌壁化学假说，该假说可以解释在缺氧、光照和避光生长响应过程中，以及在稳定生长过程中孢子囊发育的不同阶段，相关生物物理变量的观察行为。在目前的研究项目中，真菌壁化学假设得到了新的理论发现的补充，这些理论发现提供了相关生物物理变量和生物过程之间的定量关系，这些关系是膨胀生长所不可或缺的。重要的是，真菌壁化学假设以及这些新提出的定量关系可以使以前建立的用于扩张生长的定量生物物理方程与其他先前提出的用于藻类、真菌和植物细胞生长的生物模型相一致。真菌壁化学假说和新提出的定量关系将用于分析和解释刚性和肥大突变型孢子囊和野生型孢子囊的实验结果。在不久的将来，本研究的结果和基因组的测序可以为了解基因及其产物在真菌细胞扩张性生长和调节扩张性生长中的功能提供新的见解。由于孢子囊对感觉刺激表现出生长反应，该结果可以为了解基因及其产物在感觉转导通路中的功能提供新的见解。更广泛的影响提议的研究结果将整合到PI引入，开发和教授的两个新的研究生生物工程课程中：细胞生物工程I和II。参与的研究生将被鼓励教授一门本科实验课程，以便PI可以指导他们完成第一学期的课程，并培养他们的信心和教学技巧，以便他们能够更独立地教授第二学期的课程。研究生和本科生，其中包括代表性不足的群体的成员，将参与研究项目的各个方面。PI和参与的学生将为西班牙裔专业工程师协会学生分会为丹佛大都会地区的高中生和中学生举办的年度拓展会议举办讲习班。

Previous research by the Principal Investigator (PI) has derived, developed, and established quantitative biophysical equations that describe expansive growth of the large cylindrical single-celled sporangiophores of Phycomyces blakesleeanus and other cells with walls, i.e. algal, fungal, and plant cells. The objective of the current research project is to obtain insight into relationships between the biophysical variables and associated biological processes that control expansive growth and growth behavior by using mutant sporangiophores that exhibit abnormal growth behavior. The research will focus on strains of stiff and hypertropic mutant sporangiophores which exhibit weak and enhanced tropic responses and growth responses, respectively. Biophysical experiments will be conducted to determine the magnitude and behavior of relevant biophysical variables for stiff and hypertropic mutant sporangiophores. The obtained results will be compared to those of wild type sporangiophores. Research conducted for the prior NSF Grant (MCB-0640542) proposes a fungal wall chemistry hypothesis which can explain the observed behavior of relevant biophysical variables during anoxia, during light and avoidance growth responses, and for different stages of sporangiophore development during steady growth. In the current research project, the fungal wall chemistry hypothesis is complemented with new theoretical findings that provide quantitative relationships between relevant biophysical variables and biological processes that are integral to expansive growth. Importantly, the fungal wall chemistry hypothesis together with these newly proposed quantitative relationships can reconcile the previously established quantitative biophysical equations for expansive growth with other previously proposed biological models for growth of algal, fungal, and plant cells. The fungal wall chemistry hypothesis and the newly proposed quantitative relationships will be used to analyze and interpret the experimental results obtained from stiff and hypertropic mutant sporangiophores and wild type sporangiophores. In the near future, the results of the proposed research and the sequencing of the genome can provide new insight into the functions of genes and their products in expansive growth and regulation of expansive growth of fungal cells. As the sporangiophores exhibit growth responses to sensory stimuli, the results can provide new insight into the functions of genes and their products in sensory transduction pathways.Broader ImpactsThe results of the proposed research will be integrated into two new graduate bioengineering courses that the PI introduced, developed, and teaches: Cellular Bioengineering I and II. Participating graduate students will be encouraged to teach one of the undergraduate laboratory courses so that the PI may mentor them through the course for the first semester and develop their confidence and teaching skills so that they can teach the second semester more independently. Graduate and undergraduate students, which include members of underrepresented groups, will participate in all aspects of the research project. The PI and participating students will conduct workshops for the Society of Hispanic Professional Engineers student chapter's annual outreach conference for high school and middle school students in the Denver metropolitan area.