Identification And Expression Analysis Of FLOWERING LOCUS C Homologous Genes In Carya Cathayensis

Hickory (Carya cathayensis Sarg., Carya Nutt., Juglandaceae) is one of important economic trees,which is also one of very important famous dried fruit and oil tree plants in Zhejiang Province of China.It is a monoecism and diclinou plant with unisexual flowers. The order of the development of thestaminate flowers are catkin and the female flowers spica. Flowering (staminate flowers and femaleflowers) of hickory is different in space and time. The male flower buds development period caused by alarge of abscission of female flower buds, which directly affect it’s yield and quality. Study on thecharcateristics and floral of the Hickory, we had mastered differentiation and development period offemale and male flower about hickory through morphology, but floral genes regulation of Hickoryshould be for further research from molecular biology. Vernalization-related gene FLC might play role inthe plants flowering transition and regulation inhibit flower development by inhibition downstreamtarget gene. Our team had obtained the two ORFs of CcFLC by using454sequence of the female flowerbuds from Carya cathayensis. This paper will use PCR evaluation the two ORFs in female flower buds.Use Real-Time RT PCR technology and in situ hybridization analysis their mRNA expression indifferent flowering time and different issues of Hickory. For make further probe into Carya cathayensisflowering mechanism, and for fundamentally improving the Carya cathayensis production orrealization of precocious and dwarf provide the scientific basis. The main conclusions are as follows:（1）The two ORFs sequence of the CcFLC gene was checked by PCR amplification from flowerbuds of hickory, and putatively encodes a protein of212and203amino acid residues, preliminarydesignation CcFLC1（GenBank accession number JQ829074）、CcFLC2（GenBank accession numberJQ829075); Database searches revealed that the deduced amino acid sequence of CcFLC1and CcFLC2had a typical MADS-box gene domain. This indicated that CcFLC1and CcFLC2was a member ofMADS-box family. Respectively, according to the blast revealed that they had homologous78%and67%in nucleotides and amino acidses, and5’-end had higher conservative property than3’-end. Theamino acids hydrophobity analysis showed that they have more hydrophobity majority of amino acidses.Their protein would be a soluble protein without a transmembrane domain.(2) Compared with the FLC proteins reported in other plant species, the results showed thatCcFLC1and CcFLC2nucleotide sequence shares53%,57%identity with TrMADS3（ABO61200.1）ofTaihanghua., and identits to52%,56%with PpFLC（BAI99733.1），indicate that they were more closely related to TrMADS3and PpFLC. A phylogenetic tree was constructed based on amino acid sequencealignment, it is showed that CcFLC1and CcFLC2cluster as in the same branch.(3) Study of expression pattern by Real-time fluorescence quantitative PCR showed that CcFLC1and CcFLC2genes expressed in a tissue-specific manner in C. Cathayensis, but the expression ofCcFLC1was higher than CcFLC2gene. Reduced their expression were observed in flowering stalkwitch was vernalized. CcFLC1was found to be expressed highly in males and stems, a peak in femalesdifferentiation phase. CcFLC2expression was still decline as time progressed in stems, leaves, females.But there is no difference between this tissue.(4) In situ hybridization results showed that, accompanying with strong expression of CcFLC1protein in vegetative meristem on the head of development of female，CcFLC2protein expressed singlenot strong. With development of the flowering, CcFLC1hybridization signal was decreased in femaleflower primordium, axillary bud primordium and apocal meristem. But this phase expression of CcFLC2was highest in apical meristem. In short, FLC Homologous gene may be changes function that represseddevelpoment of flowering in Carya cathayensis perennial plant compare with the annual and biennialplants.