Cloning and characterization of a latex allergen (Hev b 7): homology to patatin, a plant PLA2
Cloning and characterization of a latex allergen (Hev b 7): homology to patatin, a plant PLA2
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DOI：
10.1046/j.1365-2249.1998.00596.x
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发表时间：
1998-06
影响因子：
4.6
通讯作者：
D. Kostyal;V. Hickey;J. Noti;Gordon Sussman;D. Beezhold
中科院分区：
文献类型：
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作者：
D. Kostyal;V. Hickey;J. Noti;Gordon Sussman;D. Beezhold
我们之前在乳胶中发现了一个46‐kD蛋白过敏原，其氨基酸序列与patatin基因家族同源。本研究的目的是用分子技术表征该蛋白。RNA分别从巴西橡胶树和马铃薯块茎的乳胶或叶片材料中分离得到。从氨基酸序列设计特异性聚合酶链反应（PCR）引物，逆转录酶（RT - PCR）从乳胶RNA中扩增特异性产物，随后克隆并测序。该产品全长1493 bp，开放阅读框1167 bp。推导出的氨基酸序列编码一个389 aa蛋白，pI 4.82，与烟草蛋白同源性43%。对马铃薯、橡胶树叶片和胶乳RNA的北方分析表明，该信息在胶乳中最为丰富，在橡胶树叶片中存在较弱，但未与马铃薯RNA发生杂交。Patatin具有脂质酰基转移酶和PLA2样活性，表明其作为防御相关蛋白发挥作用。乳胶中的其他防御相关蛋白质，如hevein、葡聚糖酶和hevamine也是过敏原。为了满足对乳胶的需求，橡胶树的采伐增加了防御相关蛋白的产生，这可能解释了乳胶的致敏性增加。
We previously identified a 46‐kD protein allergen in latex as having amino acid sequence homology to the patatin gene family. The objective of this study was to characterize this protein by molecular techniques. RNA was isolated from the latex or leaf material from Hevea brasiliensis and from potato tubers. Specific polymerase chain reaction (PCR) primers were designed from the amino acid sequence and reverse transcriptase (RT)‐PCR amplified a specific product from latex RNA that was subsequently cloned and sequenced. This product was 1493 bp in length with an 1167 bp open reading frame. The deduced amino acid sequence encodes for a 389 aa protein, pI 4.82 with 43% homology to tobacco patatin. Northern analysis of potato, Hevea leaf, and latex RNA demonstrated the message to be most abundant in latex, weakly present in Hevea leaf, but no hybridization occurred with potato RNA. Patatin has lipid acyl‐transferase and PLA2‐like activity, suggesting it plays a role as a defence‐related protein. Other defence‐related proteins in latex such as hevein, glucanase, and hevamine are also allergens. Increased production of defence‐related proteins as a result of increased tapping of the rubber trees to meet the demand for latex may explain the increased allergenicity of latex.