Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.31 (beta-glucuronidase)
 7,680 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The cucumber malate synthase (MS) gene, including 1856 bp of 5' non-transcribed sequence, has been transferred into Petunia (Mitchell) and Nicotiana plumbaginifolia plants using an Agrobacterium binary vector. The transferred gene is found in variable copy number in different transformants, and is stably transmitted in each case as a single Mendelian character. Transgene mRNA accumulates in the seedling during the first three days of germination, then declines in amount as the cotyledons emerge from the seed. The decline is more pronounced in light-grown seedlings than in dark-grown seedlings. Expression of the MS transgene is also detected at a low level in petals of transformed Petunia plants. In these respects the pattern of MS gene expression is similar in cucumber and in transformed plants, showing that the transferred DNA fragment contains a functional MS gene. A 1076 bp fragment of 5' sequence was linked to the beta-glucuronidase reporter gene and transferred into Nicotiana, where it was shown to direct temporal and spatial patterns of expression similar to that of the complete MS gene. However, histochemical localisation of beta-glucuronidase activity demonstrated that the chimaeric gene is expressed not only in cotyledons of transgenic plants, but also in endosperm and some hypocotyl cells during early germination. The relevance of these findings to the control of malate synthase gene expression is discussed.
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PMID:Developmental regulation of expression of the malate synthase gene in transgenic plants. 210 73

The malate synthase gene (ms) promoter in cucumber (Cucumis sativus L.) was investigated with the aim of distinguishing DNA sequences mediating regulation of gene expression by sugar, and expression following seed germination. Promoter deletions were constructed and their ability to direct expression of the beta-glucuronidase (gus) reporter gene was investigated in transgenic Nicotiana plumbaginifolia. Gene expression was assayed in germinating seeds and developing seedlings (the germination response) and in seedlings transferred from light into darkness with and without sucrose (the sugar response). As progressively more of the promoter was deleted from the 5' end, first the sugar response and then the germination response was lost. Thus, distinct regions of the promoter are required for carbohydrate control and for regulation of gene expression in response to germination. Sequence comparisons of the ms promoter with that of the isocitrate lyase gene (icl) of cucumber have previously identified four IMH(ICL-MS-Homology) sequences. One such sequence, IMH2, is shown here to be implicated in the sugar response of the ms gene. The 17 bp sequences which when deleted from the ms gene results in loss of the germination response, contains a 14 bp sequence which is similar to a sequence in the icl promoter, which we refer to as IMH5. Furthermore, this sequence has similarity with amdI9-like sequences in filamentous fungi, which confer facB-mediated acetate inducibility on several genes, including those encoding ICL and MS.
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PMID:Distinct cis-acting elements direct the germination and sugar responses of the cucumber malate synthase gene. 862 14

Malate synthase is a glyoxysome-specific enzyme. The carboxy-terminal tripeptide of the enzyme is Ser-Arg-Leu (SRL), which is known to function as a peroxisomal targeting signal in mammalian cells. To analyze the function of the carboxy-terminal amino acids of pumpkin malate synthase in plant cells, a chimeric gene was constructed that encoded a fusion protein which consisted of beta-glucuronidase and the carboxyl terminus of the enzyme. The fusion protein was expressed and accumulated in transgenic Arabidopsis that had been transformed with the chimeric gene. Immunocytochemical analysis of the transgenic plants revealed that the carboxy-terminal five amino acids of pumpkin malate synthase were sufficient for transport of the fusion protein into glyoxysomes in etiolated cotyledons, into leaf peroxisomes in green cotyledons and in mature leaves, and into unspecialized microbodies in roots, although the fusion protein was no longer transported into microbodies when SRL at the carboxyl terminus was deleted. Transport of proteins into glyoxysomes and leaf peroxisomes was also observed when the carboxy-terminal amino acids of the fusion protein were changed from SRL to SKL, SRM, ARL or PRL. The results suggest that tripeptides with S, A or P at the -3 position, K or R at the -2 position, and L or M at the carboxyl terminal position can function as a targeting signal for three kinds of plant microbody.
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PMID:Transport of chimeric proteins that contain a carboxy-terminal targeting signal into plant microbodies. 877 80