Dissecting Biomineralization by Mining the Transcriptome of Three Closely Related

描述(申请人提供)：球石生物是最壮观的钙化微藻之一。它们是浮游植物的第三大类群，有300多个现存物种，每个物种都有独特的碳酸钙细胞覆盖。虽然钙质骨骼也被称为球石，吸引了来自不同领域的科学家的注意，但缺乏与潜在生物矿化过程的功能和分子复杂性有关的信息。大分子，特别是蛋白质，协调晶体生长过程并决定球石的纳米结构的方式尚不清楚。因此，我们实验室广泛和长期的目标是了解生物矿化的分子基础，以及海洋球藻特有的方解石板的纳米级形状和图案。这项研究的主要假设是，只有通过鉴定和表征参与球石合成和组装的基因和基因产物，才能确定控制球石合成的设计原则。由于其数量丰富，分布广泛，易于培养，因此被认为是球虫的模范生物。它的基因组最近在我们的实验室和美国能源部的合作下被测序，使其能够应用各种全球方法来探索生物矿化。在这里，我们建议通过应用比较转录学的方法来剖析生物矿化和协调这一复杂过程所需的调控机制。为此，我们建议1)使用高通量454测序来询问三个姐妹物种(两个钙化物种和一个非钙化物种)在已知影响生物矿化的营养条件下的转录组，以及2)通过检查被认为对钙化过程至关重要的功能相关基因的启动子序列来识别顺式调控元件。这项工作将提供一个强大和完整的看法，生物矿化，转录组和潜在的顺式作用的调控元件。作为一项依赖于微生物学、基因组学和分子细胞生物学、生物信息学和计算生物学专业知识的合作努力，这项提议有望为致力于了解这一重要模式系统中的生物矿化调控的科学家提供宝贵的资源。 与公共健康相关：科学家和工程师渴望了解生物 管理与人类健康和技术相关的应用程序的钙化的控制。 洞察调控湖北乳杆菌这些过程的分子机制可能导致新的 促进健康矿化和解决与病理性相关的问题的战略 软骨病、肾结石、骨质疏松症和血管异位钙化等情况 纸巾。

DESCRIPTION (provided by applicant): Coccolithophores are one of the most spectacular calcifying microalgae. They are the third most prominent group of phytoplankton with over 300 extant species, each of which displays a unique calcium carbonate cell covering. While the calcareous skeletons otherwise known as coccoliths, have attracted the attention of scientists from diverse fields, information relating to the function and molecular complexity of the underlying biomineralization processes is lacking. The manner in which macromolecules, in particular proteins, orchestrate the crystal growth processes and dictate the nanoscale architecture of the coccoliths is not known. Hence, the broad and long term objective of our laboratory is to understand the molecular underpinnings of biomineralization and the nanoscale shape and patterning of the calcite plates characteristic of marine coccolithophores. The major hypothesis underlying this research is that the design principles governing the synthesis of coccoliths can only be determined by identifying and characterizing the genes and gene products involved in their synthesis and assembly. Emiliania huxleyi (E. huxleyi) is recognized as the model coccolithophore because of its abundance, cosmopolitan distribution, and the ease with which it can be cultured. Its genome was recently sequenced in a collaborative effort between our laboratory and the U.S. Department of Energy, making it feasible to apply various global approaches to explore biomineralization. We propose herein to dissect biomineralization and the regulatory mechanisms required to coordinate this complex process by applying a comparative transcriptomics approach. To this end, we proposed to 1) use high throughput 454 sequencing to interrogate the transcriptome of three sister species (two calcifying and one non-calcifying) under nutrient conditions known to affect biomineralization, and 2) to identify cis-regulatory elements by examining the promoter sequences of functionally related sets of genes deemed critical to the calcification processes. This work will afford a robust and complete view of the biomineralization transcriptome and potential cis-acting regulatory elements. As a collaborative effort that relies on expertise in microbiology, genomics and molecular cell biology, bioinformatics and computational biology, this proposal promises to provide a valuable resource for scientists working to understand the regulation and control of biomineralization in this important model system. PUBLIC HEALTH RELEVANCE: Scientists and engineers are eager to understand the biological controls that govern calcification for applications related to human health and technology. Insight into the molecular mechanisms regulating these processes in E. huxleyi may lead to new strategies to promote healthy mineralization and address problems associated with pathological conditions such as rickets, kidney stones, osteoporosis, and ectopic calcification of vascular tissues.