The 3,4-dihydroxyphenylalanine (DOPA) melanin is one of important virulence factors for Cryptococcus neoformans, which may trigger immune responses in the host. It is worth exploring the genetic function of C. neoformans, by which we may derive more antifungal strategies. Therefore, we established two systems that were constructed quickly and easily for the knock-down/knock-out of LAC1 gene: RNA interference (RNAi) and clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9. The RNAi system used pSilencer 4.1-CMV neo plasmid and short hairpin RNA to realize the effective transcriptional suppression. The CRISPR-Cas9 system used the PNK003 vectors to obtain a stable albino mutant strain. The results of phenotype, qRT-PCR, Transmission Electron Microscope (TEM) and spectrophotometry were used to assess the ability of melanin production. As a result, the RNAi system displayed attenuation of transcriptional suppression when the transformants continuously passed on new plates. However, the transcriptional suppression of long loop in short hairpin RNA were more powerful and lasted longer. The CRISPR-Cas9 system constructed an albino strain completely without the ability to produce melanin. Considering the weakening of transcriptional suppression, we recommend using a long loop for the RNAi system and 1st or 2nd passage of knockdown strains for the subsequent studies. Besides, the different capacities of melanin production might be useful for exploring the linear relation between melanin and immunoreaction of the host. In addition, we recommend applying the PNK003 vectors to other serotypes of C. neoformans for quick screening of possible trait-regulating genes because of its easy construction and valid knockout effect.

Background. Sexual transmission of human papillomavirus (HPV) types 6 and 11 causes 90% of condyloma acuminata (CA) and the prevalence of CA in the younger generation is not low. Human papillomavirus vaccines containing types 6 and 11 are highly effective in preventing condyloma acuminatum transmission. By getting immunized promptly, college students who have not had sexual experience as a catch-up group can minimize the potential emotional and financial stress of CA. However, no comprehensive research has been undertaken on the views of this population about the CA vaccination. Methods. This study aimed to examine HPV knowledge and CA vaccination acceptance among college students without sexual experience in Guangdong, China. We used WeChat web-based questionnaires to conduct a cross-sectional survey of respondents. College students identified as having never had sexual relations were maintained, and 2,139 valid questionnaires were ultimately collected. Results. Knowledge of CA (26.2%) and HPV (18.8%) was poor among college students who had never engaged in sexual activity, as was the vaccination rate (2.9%). However, acceptance of the vaccine was relatively high (54.8%). More respondents received the CA vaccine if they were full-time students (OR = 1.962), had heard of CA (OR = 1.505), had actively learned about CA (OR = 1.812), considered the vaccine safe (OR = 2.310), and believed it was successful in preventing CA (OR = 3.925). Conclusions. Overall, this population has limited knowledge about the CA and HPV vaccines. To protect young people’s health and lessen the disease burden, society should pay more attention to CA and HPV vaccination education.