Table 2.

GLRA1 matching peptide sequences identified by mass spectrometry.

>sp|P23415|GLRA1_HUMAN
MYSFNTLRLY LWETIVFFSL AASKEAEAAR $\text{SAPKPMSPSD FLDK}$LMGRTS GYDARIRPNF 60
KGPPVNVSCN IFINSFGSIA ETTMDYRVNI FLR$\text{QQWNDPR}$ LAYNEYPDDS LDLDPSMLDS 120
IWKPDLFFAN EK$\text{GAHFHEIT TDNK}$LLRISR $\text{NGNVLYSIRI TLTLACPMDL K}$NFPMDVQTC 180
IMQLESFGYT MNDLIFEWQE QGAVQVADGL TLPQFILKEE KDLR$\text{YCTKHY NTGKFTCIEA}$ 240
$\text{RFHLER}$QMGY YLIQMYIPSL LIVILSWISF WINMDAAPAR $\text{VGLGITTVLT MTTQ}\text{S}\text{SGSR}$A 300
SLPKVSYVKA IDIWMAVCLL FVFSALLEYA AVNFVSRQHK ELLRFRRKRR $\text{HHKSPMLNLF}$ 360
$\text{QEDEAGEGRF NFSAYGMGPA CLQAK}$DGISV K$\text{GANNSNTTN PPPAPSKSPE}$$\text{EMRK}$LFIQRA 420
KKIDKISRIG FPMAFLIFNM FYWIIYKIVR REDVHNQ
#	Start–End	Domain	Peptide Sequence and PTM
aO	31–44	Extracellular loop	SAPKP$\text{M}$SPSDFLDK
b	94–100	Extracellular loop	QQWNDPR
c	133–144	Extracellular loop	GAHFHEITTDNK
dO	151–171	Extracellular loop	NGNVLYSIRITLTLACP$\text{M}$DLK
dCO	151–171	Extracellular loop	NGNVLYSIRITLTLA$\text{C}$P$\text{M}$DLK
e	160–171	Extracellular loop	ITLTLACPMDLK
f	225–234	Extracellular loop, Cys-Loop	YCTKHYNTGK
fC	225–234	Extracellular loop, Cys-Loop	Y$\text{C}$TKHYNTGK
g	229–241	Extracellular loop	HYNTGKFTCIEAR
gC	229–241	Extracellular loop	HYNTGKFT$\text{C}$IEAR
hC	235–246	Extracellular loop, Cys-Loop	FT$\text{C}$IEARFHLER
i	281–299	TM2	VGLGITTVLTMTTQSSGSR
jO	351–369	Cytoplasmic loop	HHKSP$\text{M}$LNLFQEDEAGEGR
k	370–385	Cytoplasmic loop	FNFSAYGMGPACLQAK
l	392–407	Cytoplasmic loop	GANNSNTTNPPPAPSK
m	408–414	Cytoplasmic loop	SPEEMRK
mO	408–414	Cytoplasmic loop	SPEE$\text{M}$RK

Human GLRA1 protein sequence in FASTA format. Matching peptides identified by mass spectrometry experiments are highlighted. Note that the numbering for all amino acid positions cited in the text is relative to a shorter sequence lacking the first 28 amino acids, for consistency with previous homology and modeling studies. Hence I229, S267, and A288 correspond to I257, S295, and A316 in the FASTA sequence; Y410 corresponds to Y446. These four amino acids are in bold text. In the columns, peptides matching GLRA1 sequence identified with the MASCOT search engine following mass spectrometry. Sequences with amino acid residues, locations, and post translational modifications (PTM) of peptides are indicated. Specific information on peptide sequence matches for each gel band is included in Table 1. Superscripts O and C denote Oxidation and Carbamidomethylation, respectively, in the highlighted amino acid.