Soft Tissues and Cellular Features in Fossil Vertebrates

化石脊椎动物的软组织和细胞特征

• 批准号: 0541744
• 负责人: Mary Schweitzer
• 金额: --
• 依托单位: North Carolina State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-07-01 至 2011-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0541744&HistoricalAwards=false
• 关键词: Soft; Tissues; Cellular; Features; Fossil

EAR-0541744SCHWEITZERThe primary objectives of the proposed research are to: 1) identify and characterize soft tissues and cellular features preserved in multiple fossil specimens across time, and 2) test hypotheses concerning persistence of cellular and subcellular structure and molecular information in a variety of exceptionally preserved fossil specimens. This research addresses the following:Hypothesis 1: Morphological soft tissue and cellular preservation may indicate preservation of informative biomolecular fragments, such as proteins or DNA.Hypothesis 2: Organic, cellular, and molecular components within bone matrices of vertebrate tissues each degrade at different rates, and these differences can be documented by applying identical methods to fossils of varying ages.Intellectual Merit:Geochemical and biochemical investigations into degradation of molecular information in fossil specimens suggest a finite lifespan in fossils, limited to well under a million years. The lifespan and preservation potential of soft tissues and cellular structures, preserved with original transparency, flexibility and resilience"i.e., preserved as still soft tissues"have been predicted to be significantly less. And yet, recent research shows that they do persist. To understand how soft tissues and cells are preserved, it is necessary to characterize their present composition. Proposed immunochemical, spectroscopic and enzymatic analyses of components recovered from fossil specimens will identify molecules, which comprise tissues and cells. If primary (original to the source organism), their identification will clarify processes involved in degradation, preservation, and fossilization at the molecular and cellular levels, and reveal evolutionary and phylogenetic patterns. If no original material can be identified, the soft tissues indicate previously unknown geochemical processes resulting in resilient polymeric material retaining morphological and functional identity with original structures.By analyzing and characterizing these remnants in fossil specimens and comparing their compositions to that of extant vertebrate vessels, cells and bone matrix, it may be possible to identify molecular source materials from the components that remain behind, and create more accurate models of degradation pathways under naturally occurring conditions. Resulting models may then be applied to identify other fossil material with potential for recovery of informative molecular remains.Broader Impacts:Integration of research and education: The PI currently supervises 2 PhD students, one Master's student, and two undergraduates. Beginning in fall 2005, four additional graduate students will begin research projects under her direction, all of which will have an analytical component. This proposal, if awarded, will fund their research and contribute to their learning and applying new technological approaches to the study of extinct life. In addition, the PI teaches both introductory and advanced classes in dinosaur science, and includes results from ongoing research directly into lecture material.Broadening the participation of underrepresented groups: Four students (as of fall '05) working in the labs in the fall will be female, and two of these represent minority ethnic groups.Dissemination of research results: Preliminary results of experiments forming the foundation of this proposal have been published in journals that are broadly interdisciplinary, and were and will be presented at several professional meetings. In addition, the overall results have reached the public via the popular media. Data acquired during the tenure of the grant will be disseminated first via peer review processes, then made available to the general population through media outlets and longer, but less technical publications. Finally, this research will be part of permanent exhibits in both the North Carolina Museum of Natural Sciences and the Museum of the Rockies, in a format appropriate for the general public, and several other programs for public dissemination through popular media formats have been discussed.

拟议研究的主要目标是：1）识别和表征在多个化石标本中保存的软组织和细胞特征，2）测试关于细胞和亚细胞结构和分子信息在各种异常保存的化石标本中的持久性的假设。这项研究解决了以下问题：假设1：形态学软组织和细胞保存可能表明保存了信息生物分子片段，如蛋白质或DNA。假设2：脊椎动物组织骨基质中的有机，细胞和分子成分各自以不同的速度降解，这些差异可以通过对不同年龄的化石应用相同的方法来记录。对化石标本中分子信息退化的地球化学和生物化学研究表明，化石的寿命有限，仅限于一百万年以下。软组织和细胞结构的寿命和保存潜力，保持原有的透明度，灵活性和弹性“即，“作为静止的软组织保存下来”的可能性已经被预测为要小得多。然而，最近的研究表明，它们确实存在。为了了解软组织和细胞是如何保存的，有必要描述它们目前的组成。对从化石标本中回收的成分进行免疫化学、光谱和酶分析，将确定组成组织和细胞的分子。如果是原生的（来源生物的原始），它们的鉴定将澄清分子和细胞水平上的降解、保存和降解过程，并揭示进化和系统发育模式。如果没有原始材料可以确定，软组织表明以前未知的地球化学过程，导致弹性聚合物材料保留与原始结构的形态和功能特性。通过分析和表征化石标本中的这些残留物，并将其成分与现存脊椎动物的血管，细胞和骨基质进行比较，有可能从残留的成分中识别分子源材料，并建立更准确的自然条件下降解途径模型。由此产生的模型，然后可以应用于确定其他化石材料与潜在的恢复信息分子remains.Broader影响：研究和教育的整合：PI目前监督2博士生，一个硕士生，和两个本科生。从2005年秋季开始，另外四名研究生将在她的指导下开始研究项目，所有这些项目都将有分析部分。这项提案如果获得批准，将资助他们的研究，并有助于他们学习和应用新的技术方法来研究灭绝的生命。此外，PI教授恐龙科学的入门和高级课程，并将正在进行的研究结果直接纳入教材。扩大代表性不足的群体的参与：四名学生（截至2005年秋季）秋季在实验室工作的将是女性，其中两人代表少数民族。初步的实验结果形成的基础，这一建议已发表在期刊上，广泛的跨学科，并提出了和将在几个专业会议。此外，通过大众媒体向公众公布了总体结果。在赠款使用期内获得的数据将首先通过同行审议程序传播，然后通过媒体渠道和较长但技术性较低的出版物向公众提供。最后，这项研究将在北卡罗来纳州自然科学博物馆和落基山脉博物馆的永久展览的一部分，在一个适合公众的格式，并通过流行的媒体格式公开传播的其他几个方案进行了讨论。