AKo hand against shortstack

[sniplert]

Game - $0.10/$0.25 Blinds - 5 Players - (LegoPoker Hand History Converter)

SB: $16.70
Hero (BB): $47.45
UTG: $31.52
CO: $25.00
BTN: $9.86

CO posts $0.25
Preflop: Hero is dealt K[img]/images/graemlins/club.gif[/img] A[img]/images/graemlins/diamond.gif[/img] (5 Players)
<font color="red">UTG raises to $1.25</font>, CO folds, <font color="red">BTN raises to $4.35</font>, SB folds, Hero calls $4.10, UTG folds

Flop: ($10.30) 2[img]/images/graemlins/spade.gif[/img] 8[img]/images/graemlins/spade.gif[/img] 4[img]/images/graemlins/club.gif[/img] (2 Players)
Hero checks, BTN checks

Turn: ($10.30) 7[img]/images/graemlins/spade.gif[/img] (2 Players)
Hero checks, <font color="red">BTN bets all-in for $5.51</font>, Hero calls $5.51

River: ($21.32) 5[img]/images/graemlins/club.gif[/img] (2 Players - 1 All-In)

Pot Size: $21.32 ($0.84 Rake)

BTN had J[img]/images/graemlins/club.gif[/img] J[img]/images/graemlins/diamond.gif[/img] (a pair of jacks) and WON (+$10.14)
Hero had K[img]/images/graemlins/club.gif[/img] A[img]/images/graemlins/diamond.gif[/img] and LOST (-$9.86)

Villain joined table recently, no read. Need help on AKo play.