郑征帆,吕艳杰,宁黔冀
( 河南师范大学 生命科学学院,河南 新乡 453007 )
甲壳动物表皮几丁质结合蛋白结构与功能研究进展
郑征帆,吕艳杰,宁黔冀
( 河南师范大学 生命科学学院,河南 新乡 453007 )
甲壳动物;几丁质结合蛋白;结构;功能
由于坚硬表皮的限制,甲壳动物必须经过蜕皮才能生长。蜕皮是一个周期性的动态过程,包括旧表皮降解和新表皮的形成。作为表皮组成成分的几丁质是和蛋白质以结合的形式存在,此蛋白即为几丁质结合蛋白(CBPs),是甲壳动物表皮中重要的结构性蛋白,该类蛋白一般含有特征性的结构域,由蜕皮激素的靶组织——表皮上皮细胞按照一定的周期和步骤表达合成。几丁质结合蛋白与几丁质构成的复合物不仅为钙化作用提供有机支架[1],而且参与控制钙化的程度,因此,几丁质结合蛋白被认为在表皮的形成、维护以及功能的调节中起重要作用。近年来,传统的分离纯化技术、尤其是高通量测序技术的应用,大大加快了甲壳动物表皮几丁质结合蛋白新基因发现的进程,本文将在结构和功能等方面介绍此类蛋白的研究进展。
甲壳动物表皮几丁质结合蛋白分别含有特征性的保守基序,包括RR基序、富含半胱氨酸的几丁质结合结构域、postmolt-18基序、crust-18基序等。
对昆虫的研究表明,RR基序是结构性表皮蛋白中分布最广、研究最为深入的基序[2-5],首先在烟草天蛾(Manducasexta)幼虫的表皮发现[6-7]。离体研究显示,该基序能结合几丁质,覆盖35个氨基酸残基,以发现者Rebers和Riddiford的名字命名为Rebers-Riddiford共识序列,简称RR基序。首先鉴定出的是RR-1基序[Gx8Gx6YxAxExGYx7Px2P](X代表任意氨基酸,阿拉伯数字代表任意氨基酸的数目,后同),之后又发现了两个与之相似的变异型——RR-2基序[Gx8Gx6YxAx4GFNAVV]和RR-3基序[APVx2VxTxYHAODxLGOxSFGHx4OxRxEx2DAAGNKxGx8Gx6YxAxExGYx7Px2P][8]。RR-2基序N端前4个不连续的保守氨基酸与RR-1基序一致,而C端的GFNAVV代替了RR-1基序C端富含脯氨酸的序列。含RR-1和RR-2的几丁质结合蛋白在NCBI中标注为pfam00379家族[9]。根据隐马尔可夫模型发展的工具可在线提交几丁质结合蛋白的蛋白序列,更客观便捷地区分含RR-1或RR-2基序[10]。研究表明,含RR-1的几丁质结合蛋白主要来自内表皮,而含RR-2的几丁质结合蛋白主要来自外表皮[8]。RR-3基序覆盖75个氨基酸残基,C端包含RR-1基序,目前发现的含RR-3的几丁质结合蛋白种类较少,特征不够明确。
对甲壳动物表皮几丁质结合蛋白的研究远逊于昆虫,早期通常采用直接分离纯化的方法。Andersen[11]采取尿素三氟乙酸提取、离子交换层析和双向凝胶电泳等方法,从北方长额虾(Pandalusborealis)的表皮中分离纯化出一些蛋白,氨基酸组分分析表明,蛋白富含甘氨酸和丙氨酸,且大部分蛋白酸性氨基酸的含量大于15%。蛋白质序列的获得依赖于Edman降解、质谱、酶解等方法的建立,先后获得了北方长额虾表皮蛋白Hla序列[12]、美洲螯龙虾(Homarusamericanus)未钙化表皮中的6个几丁质结合蛋白序列等,对后者分析发现,这些蛋白的pI≈4,Mr≈12 ku,其中,5个蛋白仅有几个残基不一致,而另一个蛋白序列则有一半以上的差异[13];从黄道蟹(Cancerpagurus)未钙化表皮中分离纯化出5个几丁质结合蛋白,pI为3.5~10, Mr为20~43 ku[14]。这些结果反映了种内以及种间几丁质结合蛋白的多样性,也预示了这类蛋白功能的复杂性。
高通量测序等技术的应用大大加快了甲壳动物表皮几丁质结合蛋白的研究进程,越来越多的编码几丁质结合蛋白的新基因被发现,如日本囊对虾(Marsupenaeusjaponicus)的DD9A、DD9B[15]、DD5[16]和crustocalcin[17],克氏原螯虾(Procambarusclarkii)的CAP-1、CAP-2[18-20]、Casp-2[21]和SCBP-1[22],蓝蟹(Callinectessapidus)的CsAMP8.1、CsAMP6.0、CsCP8.2、CsCP8.5[23]和CsAMP9.3、CsAMP16.5、CsAMP13.4、CsAMP16.3、CsCP14.1、CsCP6.1[24]等,研究发现,除crustocalcin和CsCP6.1包含RR基序的部分序列外,上述其他几丁质结合蛋白基因均包含完整的RR-1基序。对克氏原螯虾表皮SCBP-1基因分析表明,其cDNA的1~26位为5′UTR区,第27~71位编码以起始密码子ATG为开端的信号肽序列,覆盖15个氨基酸残基,几丁质结合结构域——RR-1基序从第81位氨基酸开始至第115位氨基酸结束,覆盖35个氨基酸残基,SCBP-1共包含155个氨基酸残基,以TAA为终止密码子,3′UTR区有多聚腺苷酸信号AATAAA[22]。蓝蟹CsCP6.1的信号肽和几丁质结合结构域之间还具有跨膜区[25]。大部分几丁质结合蛋白的RR-1基序以单一非重复形式出现,但也有串联重复形式,日本囊对虾DD5蛋白在1116个氨基酸残基的ORF中,有100个氨基酸左右的串联重复单元,每个单元均包含RR-1基序[16],这种串联重复RR模式可能参与表皮中几丁质纤维的交叉连接,并且这些重复区整齐的大小可能反映了几丁质纤维有规律的空间排布。RR-2基序目前仅见于红螯螯虾(Cheraxquadricarinatus)转录物组中[26]。有关RR-3基序的报道也较少,仅在美洲螯龙虾HaCP18.8[8]和蓝蟹CsAMP/CP13.7[27]中有分布,其中,HaCP18.8在钙化表皮表达,CsAMP/CP13.7在滑动关节膜表皮和钙化表皮都有表达。
cys-CBD是富含半胱氨酸的几丁质结合结构域,分为cys-CBD1和cys-CBD2。cys-CBD1只在真菌中有报道[28],cys-CBD2在昆虫的表皮蛋白和围食膜蛋白中有分布[29],其蛋白质一级结构中的6个cys构成3个二硫键。截至目前,尚未在甲壳动物表皮分离出含有cys-CBD2的几丁质结合蛋白,但在红螯螯虾转录物组中发现了许多具有cys-CBD2的重叠克隆群[19],且红螯螯虾胃石蛋白GAP-65具有cys-CBD2[30-31],该基序在甲壳动物表皮中的分布有待进一步研究。
postmolt-18基序[VxDTPEVAAAKAAFxAAY],覆盖18个氨基酸残基,含此基序的表皮蛋白主要在蜕皮后期表达,所以称为postmolt-18基序[24]。从美洲螯龙虾钙化表皮中分离纯化出的HaCP18.8和HaCP20.2[8]、黄道蟹钙化表皮中分离纯化出的CpCP14.99和CpCP18.76[14]蛋白、蓝蟹中克隆的CsCP15.0、CsCP19.0[24]以及红螯螯虾转录物组cq post-molt protein 1[32]均含有postmolt-18基序,其中蓝蟹CsCP15.0是个例外,在蜕皮前和蜕皮后都有表达。
crust-18基序{x[L/V][I/V]GPSGIV[T/S]x[D/N]GxN[I/V]Q[V/L]},同样覆盖18个氨基酸残基,此基序只在甲壳动物表皮蛋白中发现,故称crust-18基序[14]。如9个源自美洲螯龙虾钙化表皮中的几丁质结合蛋白[24],黄道蟹钙化表皮中的CpCP 4.34、CpCP 4.59、CpCP 4.63、CpCP 4.66、CpCP 4.98、CpCP 11.58、CpCP 12.43、CpCP 12.46[14]以及红螯螯虾的两个转录物组cq crustacean CP 1和cq crustacean CP 2[32]均含有crust-18基序。crust-18基序一般以2倍或4倍的串联重复模式出现,推测可能与几丁质结合蛋白特殊折叠的空间构象有关。
几丁质结合蛋白最基本的功能是结合几丁质,形成钙沉积的网架,通常采用离体的评价方法[22]。先后从克氏原螯虾表皮中分离纯化获得的2种几丁质结合蛋白——CAP-1[18]和CAP-2[20]均有较强的几丁质结合能力。高通量测序技术的应用加快了新的几丁质结合蛋白基因发现进程,多采用大肠杆菌(Escherichiacoli)原核表达,直接评价重组蛋白的结合能力,如克氏原螯虾Casp-2的重组蛋白显示出弱的几丁质结合能力,与前期研究时较易分离相一致[21]。由于缺乏翻译后修饰或限于原核的分段表达等诸多原因,结合力的强弱并不完全与直接提取几丁质结合蛋白的难易程度一致,克氏原螯虾重组SCBP-1体外试验仅显示弱的几丁质结合能力,这与分离纯化时该蛋白强的几丁质结合能力明显不同[22]。
甲壳动物起到支持和防卫作用的坚硬表皮除了内/外表皮的结构,还与钙化有关[33-34],控制钙化是表皮几丁质结合蛋白的另一个重要功能,常规的评价方法是离体条件下过饱和CaCO3溶液中几丁质结合蛋白对CaCO3沉淀的抑制效应[18,35-37]。分离纯化的克氏原螯虾CAP-2[20]、Casp-2[21]和重组的日本囊对虾crustocalcin[17]均表现出对CaCO3沉淀的抑制,表明此类几丁质结合蛋白具有结合Ca2+的能力。构效关系的研究表明, 几丁质结合蛋白分子中丝氨酸的磷酸化与抑制活性有关,克氏原螯虾CAP-1第70位丝氨酸磷酸化后,对CaCO3沉淀的抑制活性显著提高[19]。
几丁质结合蛋白控制钙化的分子机制是目前研究的热点问题。Inoue等[20]利用同位素标记技术,研究克氏原螯虾重组CAP-1和CAP-2与45Ca2+的结合作用,结果表明此类几丁质结合蛋白可直接结合45Ca2+,推测几丁质结合蛋白可引发晶核的形成。对日本囊对虾的1种几丁质结合蛋白crustocalcin的研究表明,分段表达的N端、中间和C端重组蛋白,只有中间肽段重组蛋白结合45Ca2+[17],推测几丁质结合蛋白行使成核剂功能时具有特异的Ca2+结合位点;Endo等[38]分段表达crustocalcin蛋白,将获得的重组蛋白Fr2a(包含crustocalcin第76~210位氨基酸)和Fr3(包含crustocalcin第197~321位氨基酸)附着于直链淀粉珠表面,在含钙溶液中孵育,发现其表面有CaCO3晶体颗粒形成,且相同条件下Fr3珠比Fr2a珠表面形成的晶体颗粒数多,进一步说明了不同位点结合CaCO3的差异。甲壳动物表皮几丁质结合蛋白不仅通过引发成核来促进CaCO3晶体的形成,对晶型也有一定影响。Hennig等[39]利用鼠妇(Porcellioscaber)胸骨腹片提取的几丁质结合蛋白,体外模拟CaCO3在表皮的沉淀,SEM观察显示,与阴性对照蛋白相比,CaCO3在提取的几丁质结合蛋白中沉淀的形状与在体CaCO3球型沉淀辐射状结构十分相似。
在甲壳动物周期性蜕皮过程中,表皮结构也不断地变化,其相对稳定时期——间期表皮基本结构由外到内分别是上表皮、外表皮、内表皮、膜状层和上皮细胞层,这种变化受蜕皮激素的调节,合成几丁质结合蛋白的表皮上皮细胞是蜕皮激素的靶组织[32,40],理论上,几丁质结合蛋白的表达应该与蜕皮周期密切相关。据报道,蓝蟹、日本囊对虾和克氏原螯虾的相关基因在蜕皮前期呈高表达,而有些基因则在蜕皮后期表达[32]。
有学者利用高通量测序技术得到的大量数据建立模型,研究表明,克氏原螯虾含有RR基序的重叠克隆群在蜕皮前期D2、D4阶段有高峰[41]。上述基因表达的时序性差异可能与其编码的蛋白在表皮的分布有关,甲壳动物在蜕去旧表皮之前,新的上表皮和外表皮已经形成,在蜕皮后期,内表皮形成及表皮钙化[42-43],所以,蜕皮前期高表达的几丁质结合蛋白可能分布在外表皮,而蜕皮后期高表达的几丁质结合蛋白可能分布于内表皮[44]。
甲壳动物几丁质结合蛋白的时序性表达对于表皮结构的完整性可能至关重要,如果其中某一几丁质结合蛋白异常可能会不同程度地影响动物蜕皮周期的进程甚至引起死亡。运用RNAi技术沉默红螯螯虾Cq-M13的表达,试验组蜕皮前期的天数比对照组延长了两倍[45];沉默蓝蟹CsEarlyCP1的表达导致蜕皮前死亡率升高,免疫组化结果显示,背部表皮CsEarlyCP1的含量减少[46]。有关几丁质结合蛋白对甲壳动物表皮完整性的研究尽管目前尚未见报道,但对昆虫的观察表明,几丁质结合蛋白的缺失导致表皮超微结构异常,影响表皮的完整性。赤拟谷盗(Triboliumcastaneum)幼虫的TcCPR18和TcCPR27基因沉默,成虫表皮出现褶皱、变短[47],其中,TcCPR27缺陷个体的内表皮中,几丁质—蛋白质水平片层和垂直孔道具有异常的电子透明, TcCPR18缺陷个体的鞘翅前表皮具有无组织的片层和孔道[48-50]。
几丁质结合蛋白作为表皮中的结构性蛋白,其表达特点关乎表皮形成及结构的完整性以及各种生理功能的发挥,进而影响甲壳动物的生长、防御、免疫等各方面。虽然相当数量的表皮几丁质结合蛋白或基因相继被发现,但其确切的功能却知之甚少,如同一种几丁质结合蛋白在表皮不同钙化部位以及表皮各层(主要是外表皮和内表皮)的分布特点,不同几丁质结合蛋白对表皮完整性和蜕皮周期的影响等。另外,对于几丁质结合蛋白的探究需进一步拓宽研究的物种范围,探讨此类基因表达的调控途径及其功能诱导与阻遏等,为最终阐明蜕皮周期的分子机理奠定基础。
[1] Glazer L,Tom M,Weil S,et al.Hemocyanin with phenoloxidase activity in the chitin matrix of the crayfish gastrolith [J].Journal of Experimental Biology, 2013, 216(10):1898-1904.
[2] Togawa T,Dunn W A,Emmons A C,et al.Developmental expression patterns of cuticular protein genes with the R&R Consensus fromAnophelesgambiae[J].Insect Biochemistry and Molecular Biology, 2008, 38(5):508-519.
[3] Charles J P.The regulation of expression of insect cuticle protein genes[J].Insect Biochemistry and Molecular Biology, 2010, 40(3):205-213.
[4] Willis J H.Structural cuticular proteins from arthropods: annotation, nomenclature, and sequence characteristics in the genomics era[J].Insect Biochemistry and Molecular Biology, 2010, 40(3):189-204.
[5] Zhu K Y,Merzendorfer H,Zhang W,et al.Biosynthesis, turnover, and functions of chitin in insects[J]. Annual Review of Entomology,2016,61(1):177-196.
[6] Rebers J E,Riddiford L M.Structure and expression of aManducasextalarval cuticle gene homologous toDrosophilacuticle genes[J].Journal of Molecular Biology,1988,203(2):411-423.
[7] Rebers J E, Willis J H.A conserved domain in arthropod cuticular proteins binds chitin[J].Insect Biochemistry and Molecular Biology, 2001,31(11):1083-1093.
[8] Andersen S O.Studies on proteins in post-ecdysial nymphal cuticle of locust,Locustamigratoria, and cockroach,Blaberuscraniifer[J].Insect Biochemistry and Molecular Biology, 2000, 30(7):569-577.
[9] Tetreau G,Dittmer N T,Cao X,et al.Analysis of chitin-binding proteins fromManducasextaprovides new insights into evolution of peritrophin A-type chitin-binding domains in insects[J].Insect Biochemistry and Molecular Biology,2015,62(11):127-141.
[10] Ioannidou Z S,Theodoropoulou M C,Papandreou N C,et al.CutProtFam-Pred: detection and classification of putative structural cuticular proteins from sequence alone, based on profile Hidden Markov Models[J]. Insect Biochemistry and Molecular Biology,2014,52(5):51-59.
[11] Andersen S O. Cuticular proteins from the shrimp,Pandalusborealis[J].Comparative Biochemistry and Physiology Part B,1991,99(2):453-458.
[12] Jacobsen S L,Andersen S O,Hojrup P.Amino acid sequence determination of a protein purified from the shell of the shrimp,Pandalusborealis[J].Comparative Biochemistry and Physiology Part B,1994,109(2/3):209-217.
[13] Andersen S O.Characterization of proteins from arthrodial membranes of the lobster,Homarusamericanus[J].Comparative Biochemistry and Physiology Part A,1998,121(4):375-383.
[14] Andersen S O.Exoskeletal proteins from the crab,Cancerpugurus[J].Comparative Biochemistry and Physiology Part A,1999,123(2):203-211.
[15] Watanabe T,Persson P,Endo H, et al.Molecular analysis of two genes, DD9A and B, which are expressed during the postmolt stage in the decapod crustaceanPenaeusjaponicus[J].Comparative Biochemistry and Physiology Part B,2000,125(1):127-136.
[16] Ikeya T,Persson P,Kono M,et al.The DD5 gene of the decapods crustaceanPenaeusjaponicasencodes a putative exoskeletal protein with a novel tandem repeat structure[J].Comparative Biochemistry and Physiology Part B,2001,128(3):379-388.
[17] Endo H, Persson P, Watanabe T.Molecular cloning of the crustacean DD4 cDNA encoding a Ca2+-binding protein[J].Biochemical and Biophysical Research Communications, 2000,276(1):286-291.
[18] Inoue H,Ozaki N,Nagasawa H.Purification and structural determination of a phosphorylated peptide with anticalcification and chitin-binding activities in the exoskeleton of the crayfish,Procambarusclarkii[J].Bioscience, Biotechnology and Biochemistry,2001,65(8):1840-1848.
[19] Inoue H,Ohira T,Ozaki N,et al.Cloning and Expression of a cDNA encoding a matrix peptide associated with calcification in the exoskeleton of the crayfish[J].Comparative Biochemistry and Physiology Part B,2003,136(4):755-765.
[20] Inoue H,Ohira T,Ozaki N,et al.A novel calcium-binding peptide from the cuticle of the crayfish,Procambarusclarkii[J].Biochemical and Biophysical Research Communications,2004,318(3):649-654.
[21] Inoue H,Yuasa-Hashimoto N,Suzuki M,et al.Structure determination and functional analysis of a soluble matrix protein associated with calcification of exoskeleton of the crayfish,Procambarusclarkii[J].Bioscience, Biotechnology and Biochemistry,2008,72(10): 2697-2707.
[22] Suzuki M,Sugisaka-Nobayshi A,Kogure T,et al.Structural and functional analyses of a strong chitin-binding protein-1 (SCBP-1) from the exoskeleton of the crayfishProcambarusclarkii[J].Bioscience, Biotechnology and Biochemistry,2013,77(2):361-368.
[23] Wynn A,Shafer T H.Four differentially expressed cDNAs inCallinectessapiduscontaining Rebers-Riddiford consensus sequence[J].Comparative Biochemistry and Physiology Part B, 2005,141(3):294-306.
[24] Faircloth L M,Shafer T H.Differential expression of eight transcripts and their roles in the cuticle of the blue crab,Callinectessapidus[J].Comparative Biochemistry and Physiology Part B, 2007, 146(3):370-383.
[25] Kuballa A V,Merritt D J,Elizur A.Gene expression profiling of cuticular proteins across the moult cycle of the crabPortunuspelagicus[J].Bmc Biology,2007,5(1):1-26.
[26] Abehsera S,Glazer L,Tynyakov J,et al.Binary gene expression patterning of the molt cycle: the case of chitin metabolism[J].PloS One,2015,10(6):e0130787.
[27] Shafer T H,McCartney M A,Faircloth L M.Identifying exoskeleton proteins in the blue crab from an expressed sequence tag (EST) library[J].Integrative and Comparative Biology,2006,46(6):978-990.
[28] Wright H T,Sandrasegaram G,Wright C S.Evolution of a family of N-acetylglucosamine binding proteins containing the disulfide-rich domain of wheat germ agglutinin[J].Journal of Molecular Evolution,1991,33(3):283-294.
[29] Jasrapuria S,Arakane Y,Osman G,et al.Genes encoding proteins with peritrophin A-type chitin-binding domains inTriboliumcastaneum, are grouped into three distinct families based on phylogeny, expression and function[J].Insect Biochemistry and Molecular Biology, 2010,40(3):214-227.
[30] Shechter A,Glazer L,Cheled S,et al.A gastrolith protein serving a dual role in the formation of an amorphous mineral containing extracellular matrix[J]. Proceedings of the National Academy of Sciences of the USA,2008,105(20):7129-7134.
[31] Glazer L,Sagi A.On the involvement of proteins in the assembly of the crayfish gastrolith extracellular matrix[J].Invertebrate Reproduction and Development,2012,56(1):57-65.
[32] Roer R,Abehsera S,Sagi A.Exoskeletons across the pancrustacea: comparative morphology, physiology, biochemistry and genetics[J].Integrative and Comparative Biology,2015,55(5):771-791.
[33] Luquet G.Biomineralizations insights and prospects[J].Zookeys,2012(176):103-121.
[34] Dillaman R,Hequembourg S,Gay M.Early pattern of calcification in the dorsal carapace of the blue crab,Callinectessapidus[J].Journal of Morphology,2005,263(3):356-374.
[35] Suzuki M,Kogure T,Sakuda S,et al.Identification of ligament intra-crystalline peptide (LICP) from the hinge ligament of the bivalve,Pinctadafucata[J].Marine Biotechnology,2015,17(2):153-161.
[36] Liang J,Xu G,Xie J,et al.Dual roles of the lysine-rich matrix protein (KRMP)-3 in shell formation of pearl oyster,Pinctadafucata[J].PloS One,2015,10(7):e0131868.
[37] Dhami N K,Reddy M S,Mukherjee A.Synergistic role of bacterial urease and carbonic anhydrase in carbonate mineralization[J].Applied Biochemistry and Biotechnology,2014,172(5):2552-2561.
[38] Endo H,Takagi Y,Ozaki N,et al.A crustacean Ca2+-binding protein with a glutamate-rich sequence promotes CaCO3crystallization[J].Biochemical Journal,2004,384(1):159-167.
[39] Hennig S,Hild S,Fabritius H O,et al.Influence of near-physiological salines and organic matrix proteins from amorphous CaCO3deposits ofPorcellioscaberon in vitro CaCO3precipitation[J].Crystal Growth and Design,2012,12(2):646-655.
[40] Roer R,Dillaman R.The structure and calcification of the crustacean cuticle[J]. Integrative and Comparative Biology,1984,24(4):893-909.
[41] Tom M,Manfrin C,Chung S J,et al.Expression of cytoskeletal and molt-related genes is temporally scheduled in the hypodermis of the crayfishProcambarusclarkiiduring premolt[J].Journal of Experimental Biology,2014,217(23):4193-4202.
[42] Kuballa A V,Elizur A.Differential expression profiling of components associated with exoskeletal hardening in crustaceans[J].Bmc Genomics,2008,9(1):575-589.
[43] Kuballa A V,Holton T A,Paterson B,et al.Moult cycle specific differential gene expression profiling of the crabPortunuspelagicus[J].Bmc Genomics,2011,12(1):147-165.
[44] Nagasawa H.The crustacean cuticle: structure, composition and mineralization[J].Frontiers in Bioscience,2012,4(1):711-720.
[45] Tynyakov J,Bentov S,Abehsera S,et al.A novel chitin binding crayfish molar tooth protein with elasticity properties[J].PloS One, 2015, 10(5):e0127871.
[46] Jenkins J.Investigating the roles of cuticular proteins of the blue crab,Callinectessapidususing RNA interference[D].Wilmington:University of North Carolina,2010.
[47] Arakane Y,Lomakin J,Gehrke S H,et al.Formation of rigid, non-flight forewings (elytra) of a beetle requires two major cuticular proteins[J].PloS Genetics, 2012, 8(4):e1002682.
[48] Noh M Y,Kramer K J,Muthurkrishnan S,et al.Two major cuticular proteins are required for assembly of horizontal laminae and vertical pore canals in rigid cuticle ofTriboliumcastaneum[J].Insect Biochemistry and Molecular Biology,2014,53(4):22-29.
[49] Mun S, Noh M Y, Dittmer N T, et al.Cuticular protein with a low complexity sequence becomes cross-linked during insect cuticle sclerotization and is required for the adult molt[J].Scientific Reports,2015(5):10484.
[50] Noh M Y,Muthukrishnan S,Kramer K J,et al.TriboliumcastaneumRR-1 cuticular protein TcCPR4 is required for formation of pore canals in rigid cuticle[J].PloS Genetics,2015,11(2):e1004963.
ResearchProgressonStructureandFunctionofCrustaceanCuticularChitin-bindingProteins:aReview
ZHENG Zhengfan, LÜ Yanjie, NING Qianji
( College of Life Science, Henan Normal University, Xinxiang 453007, China )
crustacean; chitin-binding protein; structure; function
10.16378/j.cnki.1003-1111.2017.04.023
S917
C
1003-1111(2017)04-0538-05
2016-08-05;
2016-12-20.
郑征帆(1990-),女,硕士研究生;研究方向:甲壳动物生长发育的体液调节. E-mail: zhengzhengfan@163.com.通讯作者:宁黔冀(1964-),女,教授,博士;研究方向:甲壳动物激素调控. E-mail: nqjnqj1964@163.com.