Author
H. Robert Horvitz
Other affiliations: McGovern Institute for Brain Research, Howard Hughes Medical Institute, Harvard University
Bio: H. Robert Horvitz is an academic researcher from Massachusetts Institute of Technology. The author has contributed to research in topics: Caenorhabditis elegans & Gene. The author has an hindex of 92, co-authored 232 publications receiving 40527 citations. Previous affiliations of H. Robert Horvitz include McGovern Institute for Brain Research & Howard Hughes Medical Institute.
Topics: Caenorhabditis elegans, Gene, Programmed cell death, Cell, Apoptosis
Papers published on a yearly basis
Papers
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TL;DR: A new, bead-based flow cytometric miRNA expression profiling method is used to present a systematic expression analysis of 217 mammalian miRNAs from 334 samples, including multiple human cancers, and finds the miRNA profiles are surprisingly informative, reflecting the developmental lineage and differentiation state of the tumours.
Abstract: Recent work has revealed the existence of a class of small non-coding RNA species, known as microRNAs (miRNAs), which have critical functions across various biological processes. Here we use a new, bead-based flow cytometric miRNA expression profiling method to present a systematic expression analysis of 217 mammalian miRNAs from 334 samples, including multiple human cancers. The miRNA profiles are surprisingly informative, reflecting the developmental lineage and differentiation state of the tumours. We observe a general downregulation of miRNAs in tumours compared with normal tissues. Furthermore, we were able to successfully classify poorly differentiated tumours using miRNA expression profiles, whereas messenger RNA profiles were highly inaccurate when applied to the same samples. These findings highlight the potential of miRNA profiling in cancer diagnosis.
9,470 citations
TL;DR: Most miRNAs were expressed in a highly tissue-specific manner during segmentation and later stages, but not early in development, which suggests that their role is not in tissue fate establishment but in differentiation or maintenance of tissue identity.
Abstract: MicroRNAs (miRNAs) are small noncoding RNAs, about 21 nucleotides in length, that can regulate gene expression by base-pairing to partially complementary mRNAs. Regulation by miRNAs can play essential roles in embryonic development. We determined the temporal and spatial expression patterns of 115 conserved vertebrate miRNAs in zebrafish embryos by microarrays and by in situ hybridizations, using locked-nucleic acid-modified oligonucleotide probes. Most miRNAs were expressed in a highly tissue-specific manner during segmentation and later stages, but not early in development, which suggests that their role is not in tissue fate establishment but in differentiation or maintenance of tissue identity.
1,564 citations
TL;DR: The results suggest that ced-9 and bcl-2 are homologs and that the molecular mechanism of programmed cell death has been conserved from nematodes to mammals.
1,210 citations
TL;DR: Through laser ablation, chemosensory neurons that detect volatile odorants are identified and it is shown that the nematode C. elegans might have senses that correspond to smell and taste, respectively.
1,116 citations
TL;DR: The basal and enhanced slowing responses are distinct and separable neuromodulatory components of a genetically tractable paradigm of behavioral plasticity.
978 citations
Cited by
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TL;DR: Although they escaped notice until relatively recently, miRNAs comprise one of the more abundant classes of gene regulatory molecules in multicellular organisms and likely influence the output of many protein-coding genes.
32,946 citations
28 Jul 2005
TL;DR: PfPMP1）与感染红细胞、树突状组胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作�ly.
Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。
18,940 citations
TL;DR: The current understanding of miRNA target recognition in animals is outlined and the widespread impact of miRNAs on both the expression and evolution of protein-coding genes is discussed.
18,036 citations
TL;DR: To their surprise, it was found that double-stranded RNA was substantially more effective at producing interference than was either strand individually, arguing against stochiometric interference with endogenous mRNA and suggesting that there could be a catalytic or amplification component in the interference process.
Abstract: Experimental introduction of RNA into cells can be used in certain biological systems to interfere with the function of an endogenous gene Such effects have been proposed to result from a simple antisense mechanism that depends on hybridization between the injected RNA and endogenous messenger RNA transcripts RNA interference has been used in the nematode Caenorhabditis elegans to manipulate gene expression Here we investigate the requirements for structure and delivery of the interfering RNA To our surprise, we found that double-stranded RNA was substantially more effective at producing interference than was either strand individually After injection into adult animals, purified single strands had at most a modest effect, whereas double-stranded mixtures caused potent and specific interference The effects of this interference were evident in both the injected animals and their progeny Only a few molecules of injected double-stranded RNA were required per affected cell, arguing against stochiometric interference with endogenous mRNA and suggesting that there could be a catalytic or amplification component in the interference process
15,374 citations
TL;DR: Two small lin-4 transcripts of approximately 22 and 61 nt were identified in C. elegans and found to contain sequences complementary to a repeated sequence element in the 3' untranslated region (UTR) of lin-14 mRNA, suggesting that lin- 4 regulates lin- 14 translation via an antisense RNA-RNA interaction.
11,932 citations