Two genes encoded by mulberry crinkle leaf virus (MCLV): The V4 gene enhances viral replication, and the V5 gene is needed for MCLV infection in Nicotiana benthamiana.

Mulberry crinkle leaf virus (MCLV) is a member of the genus Mulcrilevirus, family Geminiviridae. The expression and functions of the V4 and V5 genes encoded by the MCLV genome remain unknown. Here, we confirmed the expression of V4 and V5 by analyzing the V4 and V5 mRNAs and the promoter activity of individual ORFs upstream sequences. The functions of V4 and V5 were investigated by constructing Agrobacterium-mediated infectious clones of wild-type MCLV variant П (MCLV vII), MCLVwt and MCLV vП mutants, such as MCLVmV4 (start codon of V4 ORF mutated), MCLVdV4 (5'-end partial deletion of V4 ORF sequence) and MCLVmV5 (V5 ORF start codon mutated). Although MCLVwt, MCLVmV4, and MCLVdV4 could infect natural host mulberry and experimental tomato plants systematically, the replication of the MCLVmV4 and MCLVdV4 genomes was obviously reduced compared to MCLVwt in both mulberry and tomato plants. MCLV vП expressing V5 could infect Nicotiana benthamiana plants systematically, but MCLVmV5 could not, implying that V5 is needed for MCLV vП to infect N. benthamiana plants. Taken together, V4 is involved in replication of the MCLV genome in host plants, and V5 potentially might extend the host range. Our findings lay a foundation for in-depth insight into the functions of MCLV-encoded proteins and provide a novel perspective for the subsequent study of MCLV-host plant interactions.

[Bamboo-based medicinal moxibustion for chronic fatigue syndrome: a randomized controlled trial].

OBJECTIVE: To observe the clinical efficacy of bamboo-based medicinal moxibustion for chronic fatigue syndrome (CFS), and to preliminarily explore its action mechanism. METHODS: Sixty-four patients with CFS were randomly divided into a moxibustion group (32 cases, 1 case dropped off, 1 case excluded) and an acupuncture group (32 cases, 2 cases dropped off). The patients in the moxibustion group were treated with bamboo-based medicinal moxibustion, while the patients in the acupuncture group were treated with routine acupuncture. Both groups were treated once a day, 6 days as a course of treatment with 1 day interval, for a total of 2 courses of treatment. Before treatment, 1 and 2 courses into treatment and in the follow-up of 14 days after treatment, the fatigue scale-14 (FS-14) and somatic and psychological health report (SPHERE) scores were observed in the two groups. Before and after treatment, the contents of CD+3, CD+4, CD+8 of peripheral blood T lymphocyte subsets were measured and CD+4/CD+8 ratio was calculated; the clinical efficacy of the two groups was compared. RESULTS: Compared before treatment, the FS-14 and SPHERE scores in the two groups were decreased 1 and 2 courses into treatment and in the follow-up (P<0.01), and the FS-14 and SPHERE scores in the moxibustion group were lower than those in the acupuncture group (P<0.01, P<0.05). Compared before treatment, the contents of CD+3, CD+4 and CD+4/CD+8 ratio in the moxibustion group were increased after treatment (P<0.01). There was no significant difference of CD+3, CD+4, CD+8 and CD+4/CD+8 ratio between before and after treatment in the acupuncture group (P>0.05). After treatment, the contents of CD+3 and CD+4 in the moxibustion group were higher than those in the acupuncture group (P<0.05). The total effective rate was 93.3% (28/30) in the moxibustion group, which was higher than 73.3% (22/30) in the acupuncture group (P<0.05). CONCLUSION: Bamboo-based medicinal moxibustion could improve the physical and mental fatigue symptoms and psychological status in patients with CFS. Its effect may be related to regulating the contents of CD+3, CD+4 of peripheral blood T lymphocyte subsets and CD+4/CD+8 ratio.

Occurrence and Pathogenicity of Hop Stunt Viroid Infecting Mulberry (Morus alba) Plants in China.

To investigate the presence of hop stunt viroid (HSVd) in mulberry (Morus alba) plants in China, HSVd was detected by reverse transcription (RT)-PCR using dsRNAs extracted from symptomatic or asymptomatic mulberry leaf samples collected from a mulberry field located in Zhenjiang, China, as a template and the primer pairs for HSVd detection. The primer pairs were designed based on the conserved sequence of 25 HSVd variants deposited in the GenBank database. Four out of a total of 53 samples were HSVd-positive, confirming that HSVd is present in mulberry plants in China. The consensus full-length nucleotide (nt) sequence of two HSVd variants determined by sequencing the HSVd variants in these four HSVd-positive samples consisted of 296 nt and shared the highest nt identity of 96.8% with that from plum in Turkey but relatively low identity with those from mulberry in Iran (87.3 to 90.8%). Phylogenetic analysis showed that these HSVd variants clustered together with those of the HSVd-hop group. Analysis of the infectivity and pathogenicity to hosts by the constructed Agrobacterium-mediated dimeric head-to-tail HSVd cDNA infectious clones demonstrated that one of the HSVd variants identified in this study infects the natural host, mulberry plants, and also infects experimental plants, cucumber, and tomato. It probably induces stunting symptoms in HSVd-infected tomatoes but does not induce symptoms on mulberry leaves or in cucumbers. Although HSVd infecting mulberry has been found in Iran, Italy, and Lebanon, this is the first study to report this viroid in naturally infected mulberry plants in China.

Whole genome sequence of mulberry crinivirus, a new member of the genus Crinivirus.

The whole genome sequence of mulberry crinivirus (MuCV), a novel member of the genus Crinivirus (family Closteroviridae) identified in mulberry (Morus alba L), was determined. The virus possesses a bipartite genome. RNA1 contains 8571 nucleotides (nt) with four open reading frames (ORFs). ORF1a encodes a putative polyprotein with papain-like protease, methyltransferase, and RNA helicase domains. ORF1b putatively encodes an RNA-dependent RNA polymerase (RdRp), which is probably expressed via a + 1 ribosomal frameshift. RNA2 consists of 8082 nt, containing eight ORFs that are similar in size and position to orthologous genes of other criniviruses. Phylogenetic analysis based on RdRp amino acid sequences of criniviruses placed MuCV in group 1.