Genome-Wide Analysis of the KANADI Gene Family and Its Expression Patterns under Different Nitrogen Concentrations Treatments in Populus trichocarpa

KANADI(KAN)is a plant-specific gene that controlled the polarity development of lateral organs.It mainly acted on the abaxial characteristics of plants to make the lateral organs asymmetrical.However,it had been less identified in woody plants.In this study,the members of the KAN gene family in Populus trichocarpa were identified and analyzed using the bioinformatics method.The results showed that a total of 8 KAN family members were screened out,and each member contained the unique GARP domain and conserved region of the family proteins.Phylogenetic analysis and their gene structures revealed that all KAN genes from P.trichocarpa,Arabidopsis thaliana,and Nicotiana benthamiana could be divided into four subgroups,while the eight genes in P.trichocarpa were classified into three subgroups,respectively.The analysis of tissue-specific expression indicated that PtKAN1 was highly expressed in young leaves,PtKAN6 was highly expressed in young leaves and mature leaves,PtKAN2,PtKAN5,and PtKAN7 were highly expressed in nodes and internodes,PtKAN8 was highly expressed in roots,and PtKAN3 and PtKAN4 showed low expression levels in all tissues.Among them,PtKAN2 and PtKAN6,and PtKAN4 and PtKAN5 might have functional redundancy.Under high nitrogen concentrations,PtKAN2 and PtKAN8 were highly expressed in mature stems and leaves,respectively,while PtKAN4,PtKAN5,and PtKAN7 were highly expressed in roots.This study laid a theoretical foundation for further study of the KAN genemediated nitrogen effect on root development.

A new LFSR based high-frequency test method for RSFQ circuit

Rapid single flux quantum(RSFQ)circuits have the advantages of high speed and low power consumption.The typical frequency of the RSFQ circuits is tens of GHz.Therefore,it is necessary to reliably test the highfrequency performance of RSFQ circuits simply and effectively.This paper proposes a new on-chip highfrequency testing method,which uses pseudo-random sequences generated by linear feedback shift register(LFSR)as the test vectors,and the output shift registers(SRs)to store the last piece of high-frequency testing result and read out it at low-frequency.Unlike the traditional high-frequency demonstration method of using the Input/Output SRs,our testing system can automatically generate a large number of test vectors to test the circuit at high frequency at low cost,making the whole high-frequency demonstration more reliable and convincing.On the other hand,this method is also a feasible and straightforward on-chip high-frequency test method for various RSFQ circuits.This work verified the proposed method,and the highest test frequency can reach 54 GHz while the circuit shows good operating margins.