Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| ↓ Function / Genus → | Shigella | Salmonella | Yersinia | Escherichia |
| --- | --- | --- | --- | --- |
| Needle monomer | MxiH | PrgI | YscF | EscF |
| Inner rod | MxiI | PrgJ | YscI | EscI |
| Needle-tip protein | IpaD | SipD | LcrV | EspA |
| Translocator | IpaB | SipB | YopB | EspD |
| Translocator | IpaC | SipC | YopD | EspB |
| Chaperone for the two translocators | IpgC | SicA | SycD | CesD |
| ATPase | Spa47 | InvC | YscN | SepB (EscN) |
| Ruler protein | Spa32 | InvJ | YscP | Orf16 |
| Switch | Spa40 | SpaS | YscU | EscU |
Question:
what's the ↓ function / genus → with shigella being spa32
Answer:
Ruler protein