The correct way to build search term for high-specificity search in NCBI (nuccore)

Question

[chun.c.yeung]

I am experimenting ways to refine my search results to match what I really want. Suppose I want to search this record: https://www.ncbi.nlm.nih.gov/nuccore/NR_125700.1/ or other similar records from the search bar, I use the search term: "Kastovskya adunca[ORGN] AND 16S[ALL]", it returns me some results but not specific enough (I use ALL for 16s because I dont know what is the correct search field to use for sequence type, I suppose ALL include all search fields, please correct me if it is wrong).

To be more specific, suppose I am especially interested in records with a location information i.e. "lat_lon=" exist in the Features/source of the annotation table which is found in the link above. Then I tried to search with "Kastovskya adunca[ORGN] AND 16S[ALL] AND lat_lon=[ALL]" (I also tried FKEY as search field) but it returns me with no result. What has gone wrong here?

Thank you very much.

Answer 1

[vkkodali_ncbi]

You can search for all rRNAs using "biomol rrna"[Properties] and location information using "lat lon"[Properties]. However, it appears that the location search works only if it is present as part of the MIGS-Data like it is in the case of NR_074955.1.

[chun.c.yeung]

Thank you for your answer. As you said, it does not work for lat_lon not showing as part of MIGS-Data and the majority of records seem not to have MIGS-Data associated with it. Location information is very important for my research so let's see if somebody has another idea. I am surprised there seems to be a significant lack of location information for most records.

[vkkodali_ncbi]

let's see if somebody has another idea

Consider asking RefSeq helpdesk directly.