Supplementary Table 4 - Strains and primers from <i>mmi1</i> and <i>rep2</i> mRNAs are novel RNA targets of the Mei2 RNA binding protein during early meiosis in <i>Schizosaccharomyces pombe</i>

The RNA-binding protein Mei2 is crucial for meiosis in <i>Schizosaccharomyces pombe.</i> In <i>mei2</i> mutants, pre-meiotic S-phase is blocked, along with meiosis. Mei2 binds a long non-coding RNA (lncRNA) called meiRNA, which is a ‘sponge RNA’ for the meiotic inhibitor protein Mmi1. The interaction between Mei2, meiRNA and Mmi1 protein is essential for meiosis. But <i>mei2</i> mutants have stronger and different phenotypes than meiRNA mutants, since <i>mei2Δ</i> arrests before pre-meiotic S, while the meiRNA mutant arrests after pre-meiotic S but before meiosis. This suggests Mei2 may bind additional RNAs. To identify novel RNA targets of Mei2, which might explain how Mei2 regulates pre-meiotic S, we used RNA Immunoprecipitation and Cross-linking Immunoprecipitation. In addition to meiRNA, we found the mRNAs for <i>mmi1</i> (which encodes Mmi1) and for the S-phase transcription factor <i>rep2</i>. There were also three other RNAs of uncertain relevance. We suggest that at meiotic initiation, Mei2 may sequester <i>rep2</i> mRNA to help allow pre-meiotic S, and then may bind both meiRNA and <i>mmi1</i> mRNA to inactivate Mmi1 at two levels, the protein level (as previously known), and also the mRNA level, allowing meiosis. We call Mei2–meiRNA a ‘double sponge’ (i.e. binding both an mRNA, and its encoded protein).

RNA结合蛋白Mei2对粟酒裂殖酵母（*Schizosaccharomyces pombe*）的减数分裂至关重要。在*mei2*突变体中，减数分裂前S期（pre-meiotic S-phase）与减数分裂过程均会被阻滞。Mei2可结合一种名为meiRNA的长链非编码RNA（long non-coding RNA，lncRNA），后者是减数分裂抑制蛋白Mmi1的“海绵RNA”。Mei2、meiRNA与Mmi1蛋白三者间的相互作用对减数分裂必不可少。但*mei2*突变体的表型相较于meiRNA突变体更为显著且存在差异：*mei2Δ*缺失突变体阻滞于减数分裂前S期之前，而meiRNA突变体则阻滞于减数分裂前S期之后、减数分裂起始之前。这提示Mei2可能还可结合其他RNA。为鉴定Mei2的新型RNA靶标以阐明其调控减数分裂前S期的分子机制，我们采用了RNA免疫沉淀（RNA Immunoprecipitation）与交联免疫沉淀（Cross-linking Immunoprecipitation）技术。除meiRNA外，我们还检测到了编码Mmi1的*mmi1*信使RNA（mRNA），以及S期转录因子*rep2*的信使RNA，此外还有3种相关性尚不明确的RNA。我们推测，在减数分裂起始阶段，Mei2可能通过隔离*rep2*的信使RNA以促进减数分裂前S期的顺利进行；随后可同时结合meiRNA与*mmi1*的信使RNA，从两个层面使Mmi1失活：一是如先前已知的蛋白层面，二是信使RNA层面，进而允许减数分裂进程正常开展。我们将Mei2与meiRNA的这种组合称为“双海绵”（double sponge），即其可同时结合一种信使RNA及其编码的蛋白。

搜集汇总

背景与挑战

背景概述

该数据集是一个补充表格，包含与mmi1和rep2 mRNA相关的菌株和引物信息，这些mRNA是裂殖酵母减数分裂早期Mei2 RNA结合蛋白的新靶标。数据集支持一项研究发现，即Mei2通过结合这些mRNA来调控前减数S期和减数分裂过程，为理解减数分裂机制提供了实验数据。