Yesterday, I downloaded a human lncRNA fasta file from Genecode to find out if my presumably-novel-lncRNA-sequence exists in the database. I tried to find the sequence using simple linux commands like 'grep', and it seemed like it didn't exist. I don't want to jump into the conclusion, yet.... SO what I'm really looking for is any kinds of tools (e.g. scripts, UNIX commands, websites, and etc.) that can confirm my previous results.
FYI, I'm not capable to make my own scripts.